Óscar Gutiérrez was born on December 11, 1974 in Chula Vista, California.

Gutiérrez made his debut in Mexico on April 30, 1989, when he was 14 years old. He was trained by his uncle Rey Misterio Sr. and wrestled early on in Mexico where he learned the Lucha Libre high flying style that has been his trademark. He had ring names such as “La Lagartija Verde (The Green Lizard)” and “Colibrí (Humming bird)” before his uncle gave him the name of Rey Misterio Jr. In 1991, Mysterio was awarded “Most Improved Wrestler” in Mexico while wrestling as Colibrí.

Mysterio signed with Paul Heyman’s Extreme Championship Wrestling (ECW) in 1995. He debuted in September at Gangstas Paradise, defeating Psicosis, who was also making his ECW debut. A feud between the two began, which included a two out of three falls match and a Mexican Death match. Mysterio also had a series of matches with ECW-newcomer Juventud Guerrera during early 1996. He wrestled his final bout for ECW at Big Ass Extreme Bash in March 1996.

Mysterio made his World Championship Wrestling (WCW) debut on June 16, 1996, at The Great American Bash, challenging Dean Malenko for the WCW Cruiserweight Championship, which Malenko retained by winning. In July at Bash at the Beach, he defeated longtime rival Psicosis in a number one contender’s match to earn another opportunity at the Cruiserweight title. The next night, on the July 8 episode of WCW Monday Nitro, he defeated Malenko to win his first Cruiserweight Championship. He reigned as champion for three months, which included title defenses against the likes of Ultimate Dragon, Malenko, and Super Caló before he lost the title to Malenko at Halloween Havoc. Following his Cruiserweight Championship reign, Mysterio challenged Ultimate Dragon for the J-Crown Championship, but was unsuccessful in his title match at World War 3 in November.

In early 1997, he feuded with Prince Iaukea over the WCW World Television Championship. Mysterio was defeated in his title match against Iaukea at SuperBrawl VII after Lord Steven Regal attacked him. Mysterio also lost a championship rematch at Uncensored in March. Mysterio soon began a feud with the New World Order (nWo), which culminated when he lost a Mexican Death match to nWo member Konnan at Road Wild in August. Mysterio then became involved in a feud with his real-life friend and Cruiserweight Champion Eddie Guerrero. He defeated Guerrero in a Title vs. Mask match at Halloween Havoc to win the Cruiserweight Championship for the second time. On the November 10, 1997, episode of Nitro, he lost the title back to Guerrero. They had a rematch at World War 3, which Mysterio also lost.

In 1999, after the two factions of nWo reformed, they demanded that the LWO disband. Mysterio refused to take off his LWO colors and was attacked by the nWo as a result. This led to a match at SuperBrawl IX where Mysterio and tag partner Konnan lost a “Hair vs. Mask match” against Kevin Nash and Scott Hall, forcing Mysterio to remove his mask. After the match, he phoned his uncle to tell him the news. Mysterio has publicly expressed his disappointment over being unmasked:

On the October 18 episode of Nitro, Mysterio and Konnan teamed up together to defeat Harlem Heat for the World Tag Team Championship. Mysterio, however, was injured during the match and was sidelined as a result. Billy Kidman substituted for Mysterio and teamed with Konnan during their title defense against Harlem Heat and The First Family, in which the Filthy Animals went on to lose the title back to Harlem Heat. Mysterio returned in early 2000 and remained a steady performer, eventually joining the New Blood faction in early 2000 opposing the Millionaire’s Club. On the August 14 episode of Nitro, Mysterio and Juventud defeated The Great Muta and Vampiro to win the World Tag Team Championship. They were stripped of the title after Ernest Miller pinned Disco Inferno with the stipulation that if he pinned Disco, Mysterio and Guerrera would be stripped of the title. The Filthy Animals then feuded with The Natural Born Thrillers in the fall of the year. At Fall Brawl, the Filthy Animals fought the Thrillers to a no contest in an Elimination tag team match. Mysterio reformed his tag team with Kidman and the two challenged for the World Tag Team Championship in a Triangle match at Halloween Havoc, facing the champions Natural Born Thrillers and The Boogie Knights, where the Thrillers retained.

Mysterio appeared in the 2000 film Ready to Rumble along with several other wrestlers.

Upon his return to the USA, he worked in IWA Mid-South, the Xcitement Wrestling Federation and the Heartland Wrestling Association, with the likes of Eddie Guerrero and CM Punk. Mysterio traveled to Puerto Rico for the World Wrestling Council and wrestled Eddie (Primo) Colon over the WWC World Junior Heavyweight Championship in early 2002.

In June 2002, Mysterio signed with World Wrestling Entertainment (WWE), and promos that hyped his debut began airing. The “Jr.” was dropped from his name and was billed simply as Rey Mysterio. At the insistence of Vince McMahon, Mysterio agreed to wear his mask again. While this angered lucha libre fans in Mexico as it violated tradition, Mysterio did receive permission from an official lucha libre commission to wear his mask again, as he had not lost his mask in a traditional mask vs. mask match. WWE has normally censored footage of Mysterio being unmasked in WCW for kayfabe-based reasons. However, when WWE Classics on Demand rebroadcast WCW Sin in April 2013, a match featuring Mysterio unmasked was left intact.

The match at WrestleMania was part of a storyline in which Guerrero turned on Mysterio and beat him up after abandoning him during a match against MNM for the Tag Team Championship. Then after a no disqualification match against Chavo, Eddie came out and slammed Mysterio on the steel steps, displaying Eddie’s increasing frustration with being unable to defeat Mysterio. Guerrero and Mysterio continued to feud, with Guerrero threatening to reveal a secret he and Mysterio shared involving Mysterio’s real life son Dominik, unless Mysterio deferred to Guerrero’s authority. Guerrero later revealed that, in the storyline, he was Dominik’s biological father. The storyline went that Guerrero knew Mysterio was having trouble starting his own family, so Guerrero left Dominik as a baby with Mysterio and his wife Angie to raise. In subsequent weeks, Guerrero threatened to take custody of Dominik, drawing up custody papers and having his lawyer present them to Mysterio. At SummerSlam, Mysterio defeated Guerrero in a ladder match for the custody of Dominik. Their feud ended when Guerrero gained a victory over Mysterio in a steel cage match. On November 13, 2005, Eddie Guerrero was found dead in his hotel room in Minneapolis, Minnesota. That same day at a WWE “Super Show” where SmackDown! and Raw were both taped, Mysterio gave an emotional speech about Guerrero, and in a show of respect removed his mask (though he put his head down, so no one could see his face). Mysterio went on to defeat Shawn Michaels in an interpromotional match later that night. After the match, Michaels and Mysterio hugged in the ring and Mysterio pointed up to the sky, crying, in memory of Guerrero.

Gutierrez and his wife Angie have two children: a son, Dominik (born April 5, 1997) and a daughter, Aalyah (born August 20, 2001). He has tattoos of his children’s names on his right and left biceps, tattoos dedicated to his wife, Angie, and a tattoo with the initials EG for his best friend and fellow wrestler, Eddie Guerrero, who died in 2005. He is a devout Roman Catholic, frequently crossing himself before his matches and bearing numerous religious tattoos on his body, most notably a cross on his chest attached to rosaries as well as other crosses and allusions to God.

Mysterio was the second entrant in the 2006 Royal Rumble match. He won the match and earned a world title shot, last eliminating Randy Orton. He lasted 62 minutes, a Royal Rumble record. Orton urged him to put the title shot at stake in a match at No Way Out. In the weeks preceding No Way Out, Orton made disparaging remarks about Eddie Guerrero. Many fans felt the comments were unwarranted and distasteful in the wake of Guerrero’s death in November 2005. Orton won at No Way Out, earning Mysterio’s title shot for the World Heavyweight Championship at WrestleMania 22. General Manager Theodore Long re-added Mysterio to the WrestleMania title match however, making it a Triple Threat match between Orton, Mysterio, and then-champion, Kurt Angle. At WrestleMania, Mysterio pinned Orton to become the new World Heavyweight Champion. On the following episode of SmackDown!, Mysterio – who was billed as being an “underdog champion”, made his first successful World Heavyweight title defense against Orton. Mysterio went on to retain his title again during a WrestleMania rematch on SmackDown! against Angle three weeks later.

Mysterio made his in-ring return at SummerSlam on August 26, 2007, defeating Guerrero, after Guerrero obsessed over Mysterio’s return as well as wanting to injure Mysterio again. On the August 31 episode of SmackDown!, Mysterio won a “Championship Competition” to become the number one contender for the World Heavyweight Championship, defeating Batista and Finlay. On the September 7 episode of SmackDown!, Mysterio had an “I Quit” match with Guerrero, which he won after hitting Guerrero’s knee with a steel chair repeatedly in a similar manner to which Mysterio had been put out of action, to end the feud. Mysterio then began a feud with The Great Khali, which led to a World Heavyweight Championship match at Unforgiven. The match was later made a Triple Threat match, also involving Batista, who won it.

Mysterio has been a subject of several DVDs during his wrestling career, including Rey Mysterio: 619, a 2003 documentary of Mysterio’s career and personal life. WWE also produced Rey Mysterio: The Biggest Little Man, a three disc set featuring Mysterio’s best matches that was released on October 23, 2007. He was also featured on the DVD Before They Were Wrestling Stars: Rey Mysterio Jr. in 2007 which featured matches from his time in Mexico. Rey Mysterio: The Life of a Masked Man was issued on July 12, 2011. In the UK, Silver Vision released a Mysterio DVD as part of their Best of WWE collection. This featured his matches from SummerSlam 2005, WrestleMania 22, No Mercy 2006, and SummerSlam 2007.

On March 19, 2007, Sports Illustrated posted on its website an article in its continuing series investigating a steroid and HGH ring used by a number of professional athletes in several sports. That article mentioned several current and former WWE wrestlers, including Gutierrez who was alleged to have obtained nandrolone and stanozolol. WWE subsequently stated that the allegations preceded the Talent Wellness program WWE launched in February 2006. On August 27, 2009, WWE announced that Gutierrez would receive a 30-day suspension due to a violation of the wellness program. Days later Gutierrez defended himself in a newspaper interview by explaining the drugs as being on a prescription for his knee and arm. While the Wellness Policy allows for prescribed drugs, Gutierrez further contested he had been on a family holiday and subsequently in Europe promoting SummerSlam, giving him only a day to provide the prescription after being notified. On April 26, 2012, WWE suspended Gutierrez for 60 days due to a second violation of their wellness program.

Mysterio made his return on the June 23, 2008, episode of Raw, as the first wrestler to be drafted in the 2008 WWE Draft from SmackDown brand to the Raw brand. Mysterio made his Raw in-ring debut on July 7, pinning Santino Marella after a 619. General Manager Mike Adamle announced that John Cena was injured and that Mysterio would replace him in the Championship Scramble at Unforgiven. The next week, Mysterio made his return to Raw after an extended absence by attacking Kane, turning back numerous claims that Kane had “ended his career”. Mysterio then made his in-ring return at Unforgiven, competing in the World Heavyweight Championship scramble match, which was won by Chris Jericho. Mysterio put his mask on the line in a singles match at No Mercy, which he won by disqualification after Kane attacked him with a steel chair. He defeated Kane again at Cyber Sunday, this time in a No Holds Barred match, and again at Survivor Series, when the pair were on opposing sides in a five-on-five elimination match. Mysterio participated in the 2009 Royal Rumble match, entering first and spending 49 minutes and 24 seconds in the match, before being eliminated by Big Show. The following night on Raw, he qualified for the Elimination Chamber match for the World Heavyweight Championship at No Way Out, but was eliminated by Edge when the two were the last men in the Chamber match.

Mysterio returned from his suspension at Hell in a Cell, teaming with former tag team partner Batista to face Jeri-Show (Chris Jericho and Big Show) for the Unified WWE Tag Team Championship. They failed to win the titles, as Mysterio was punched and pinned by Big Show. At Bragging Rights, Mysterio was unsuccessful in winning the World Heavyweight Championship in a Fatal Four-Way match involving Batista, CM Punk, and then-champion The Undertaker. During the match, Mysterio broke up Batista’s pin on Undertaker costing him the match and the title. After the match, Batista attacked Mysterio, ending their alliance. Mysterio faced Batista at Survivor Series, where he lost by referee stoppage after Batista performed three Batista Bombs on him. Mysterio lost to Batista again in a street fight on the December 11 episode of SmackDown. A week later Mysterio defeated Batista and was named the number one contender for the World Heavyweight Championship, but his title match against The Undertaker on the December 25 episode of SmackDown ended in a no contest after Batista interfered. On January 1, 2010, Mysterio participated in a Beat the Clock Tournament for a World Heavyweight Championship match at the Royal Rumble. In the tournament, he defeated his former rival Chris Jericho in the quickest time, and prevented Batista from beating it by interfering in his match. This led to a number one contender’s match between the duo the following week, which also ended in a no contest following interference from the Undertaker. The following week in a re-match, Mysterio defeated Batista in a Steel Cage match, but failed to win the championship at the Royal Rumble.

In the 2011 WWE Draft, Mysterio was drafted to the Raw brand. On the May 9 episode of Raw, Mysterio lost a triple threat match to determine the number one contender for the WWE Championship. Following the match, Mysterio was attacked by R-Truth, which led to a match between the two at Over the Limit, which R-Truth won. In May, Mysterio started feuding with CM Punk, with the pair exchanging victories on consecutive episodes of Raw. The feud culminated in a singles match on June 19 at Capitol Punishment, where Punk emerged victorious. On July 17 at Money in the Bank, Mysterio failed to capture the Raw Money in the Bank briefcase, as the match was won by old rival Alberto Del Rio. The following night on Raw, Mysterio took part in a tournament for the vacant WWE Championship and advanced to the finals. On the July 25 episode of Raw, Mysterio defeated The Miz in the final to win his first WWE Championship, but he lost the title to John Cena later that night. On August 15, Mysterio received a rematch for the WWE Championship against new champion Alberto Del Rio, but lost via submission. Mysterio suffered an injury in late August. Mysterio returned at the Slammy Awards to present the Superstar of the Year Award to CM Punk.

On April 26, 2012, WWE reported that Mysterio had been suspended for 60 days due to his second violation of the company’s Talent Wellness Program policy and that his suspension would expire on June 25.

After an absence of almost a year, Mysterio returned on the July 16 episode of Raw, saving Zack Ryder from his old rival, Alberto Del Rio. On August 19 at SummerSlam, Mysterio unsuccessfully challenged The Miz for the Intercontinental Championship. During the match, Mysterio suffered a legitimate concussion, rendering him inactive for a week, but he returned to SmackDown on the August 31 episode. On September 16 at Night Of Champions, Mysterio failed again to capture the Intercontinental Championship from The Miz in a fatal four-way match, also involving Cody Rhodes and Sin Cara. The following night on Raw, Mysterio and Sin Cara teamed up to defeat Primo and Epico in a tag team match, after which they were attacked by The Prime Time Players (Darren Young and Titus O’Neil). According to Mysterio, he took the decision to leave WWE when he saw no creative direction about his tag team with Sin Cara. In October, Mysterio and Sin Cara entered a tournament to determine the number one contenders to the WWE Tag Team Championship, defeating Primo and Epico in the first round and the Prime Time Players in the semi-finals. Mysterio and Sin Cara were set to face the team of Cody Rhodes and Damien Sandow on the October 15 episode of Raw, but the match was postponed due to Mysterio legitimately suffering from effects of the stomach flu. The final took place the following week, on October 22, where he and Sin Cara were defeated by Rhodes and Sandow. On November 18 at the Survivor Series pay-per-view, Mysterio and Sin Cara were victorious in a 10-man elimination tag team match alongside Brodus Clay, Justin Gabriel, and Tyson Kidd against Primo, Epico, the Prime Time Players, and Tensai. On December 16 at TLC: Tables, Ladders & Chairs, Mysterio and Sin Cara were defeated by Team Rhodes Scholars (Cody Rhodes and Damien Sandow) in a number one contenders Table match for the WWE Tag Team Championship. Two days later on SmackDown, Mysterio was sidelined with a storyline injury when he and Sin Cara were attacked by The Shield. This was used to write them off television, as Mysterio was taking some time off, and Sin Cara underwent a knee surgery. Mysterio returned on January 27, 2013, at the Royal Rumble, entering the Royal Rumble at number fourteen but was eliminated by Wade Barrett. In March, Mysterio took another leave of absence due to a legitimate knee injury, explained in storyline as an attack by Mark Henry.

After eight months, Mysterio returned at a WWE live event on October 17, 2013, and returned to television as part of the Spanish commentary team at Hell in a Cell. On the November 18 episode of Raw, Mysterio saved CM Punk and Daniel Bryan from an attack by The Wyatt Family and The Real Americans (Jack Swagger and Antonio Cesaro), which led to Mysterio being part of a 10-man elimination tag team match at Survivor Series in which Mysterio’s team lost after he was eliminated by sole survivor Roman Reigns. At TLC: Tables, Ladders and Chairs, Mysterio teamed with Big Show to unsuccessfully challenge Cody Rhodes and Goldust for the WWE Tag Team Championship in a fatal four-way match also involving RybAxel (Ryback and Curtis Axel) and The Real Americans. At the Royal Rumble pay-per-view on January 26, 2014, Mysterio entered the Royal Rumble match at #30, but was eliminated by Seth Rollins. At WrestleMania XXX, Mysterio competed in the André the Giant Memorial Battle royal but was eliminated by Cesaro. He appeared on the April 7 episode of Raw, losing to a returning Bad News Barrett and subsequently decided to take time off to heal a wrist injury.

During his hiatus, it was reported that Mysterio wanted to leave WWE, but the promotion had extended his contract without his approval. Mysterio did not return to WWE programming, and instead appeared in a video message at AAA’s Triplemanía XXII and also visited Lucha Underground. On February 26, 2015, WWE officially announced that Mysterio’s WWE contract had expired, ending his nearly 13-year tenure with the company.

On March 3, 2015, five days after being released from WWE, it was announced that Mysterio had agreed to work for Lucha Libre AAA Worldwide for the first time since 1995. He made his in-ring return as part of AAA’s 2015 pay-per-view Rey de Reyes (“King of Kings”) on March 18, 2015. Mysterio teamed up with Myzteziz (formerly Sin Cara in WWE) to defeat the Los Perros del Mal team of El Hijo del Perro Aguayo and Pentagón Jr., with Mysterio scoring the winning pin. This match is notorious for showing wrestler Perro Aguayo Jr.’s death in the ring following a drop kick from Mysterio. Mysterio delivered a dropkick to Perro’s back, causing him to fall to the second rope, setting him up for Mysterio’s signature “619” wrestling move, which involve Mysterio running towards the rope, grabbing it, and spinning around 180°, hitting the person on the face with his legs. Mysterio, seeing that something was wrong due to Perro becoming limp, purposely missed. The other wrestlers continued performing while each coming up and checking on Perro. They quickly finished the match after realizing that something serious had happened. The ref, wrestlers, and lockerroom crew came out and took Perro out using a piece of plywood. He was pronounced dead by the doctors later that night. His official death was ruled as cardiac arrest.

On May 24, 2015, Mysterio came together with Myzteziz and El Patrón Alberto to form the “Dream Team” for AAA’s Lucha Libre World Cup. The trio eventually won the tournament, defeating Johnny Mundo, Matt Hardy and Mr. Anderson in the finals with Mysterio pinning Mundo for the win. For Triplemanía XXIII, AAA’s biggest show of the year, a “dream match” between Mysterio and Myzteziz took place. Both wrestlers teamed during their time in WWE and AAA but had never competed against each other. Mysterio was victorious, forcing Myzteziz to submit to a Fujiwara armbar. After the match, Myzteziz turned rudo and sprayed mist at Mysterio’s face and challenged him to a Lucha de Apuestas. In early February 2016, AAA announced that Mysterio had left AAA due to financial issues between Mysterio and AAA. Despite not working directly for AAA, Mysterio Jr. participated in the 2016 Lucha Libre World Cup alongside Dr. Wagner Jr. and Dragon Azteca Jr., known as “Team Mexico International” the trio finished in third place.

Mysterio signed with Lucha Underground on December 12, 2015 and appeared on the second season. On January 10, 2016, Mysterio teamed with Dragon Azteca Jr. and Prince Puma to defeat Ivelisse, Johnny Mundo and Son of Havoc and Fénix, Jack Evans, and PJ Black and Cortez Castro, Joey Ryan and Mr. Cisco in a 4-way Trio Tag Team Elimination Match for the Lucha Underground Trios Championship. Mysterio was the second competitor to enter the second ever Aztec Warfare match and was the final elimination by the eventual winner Matanza. On January 31, 2016, at Ultima Lucha Dos, Rey Mysterio defeated Prince Puma in a singles match. Mysterio defeated Chavo Guerrero Jr. in a Loser Leaves Match. On April 9, 2016 Mysterio was in an Aztec Warfare match where he eliminated Matanza Cueto after Mysterio was eliminated by Johnny Mundo.

On March 20, 2015, Mysterio partnered with Extreme Tiger in a match against the tag team of Perro Aguayo Jr. and Manik. Mysterio scored the winning pin on Manik while all involved were unaware that Aguayo was dead (rather than just knocked out) following a dropkick to Aguayo by Mysterio to the middle rope. Mysterio then attempted the 619 on Aguayo and Manik, but did not connect. Aguayo was rushed to a hospital and doctors attempted to revive him, officially pronouncing him dead at 1:00 AM on March 21.

Mysterio faced fellow WWE alumnus Kurt Angle on March 20, 2016 for the upstart URFight promotion. Mysterio successfully defeated Angle in a two-falls match with assistance from rapper Riff Raff. In January 2017, Mysterio noted in an interview that he may consider opening up his own wrestling school. During the interview, he said: “I just thought I would never have the time. Now being able to make that time – to not have the busy schedule I had with WWE – gives me plenty of time to be a family man. I’m hoping that this time I’m spending with my son will open up that idea again and create a Rey Mysterio Wrestling school”. On April 30, 2017, at the WCPW Pro Wrestling World Cup – Mexican Qualifying Round, Mysterio won the Mexico Leg with Penta El Zero M defeating Alberto El Patron in the semi-finals, and defeating longtime rival Juventud Guerrera in the finals. In Round 16, Mysterio lost to the English qualifier Will Ospreay.

During an interview with Title Match Wrestling in December 2016, Mysterio was asked if he would ever return to WWE, Mysterio replied:

Rey Mysterio teamed up with Mexican luchadors Fenix and Bandido for the main event of the indy super show All In on September 1, 2018. The trio lost to The Golden Elite team of Kota Ibushi and The Young Bucks (Nick and Matt Jackson).

Rey Mysterio made his New Japan Pro-Wrestling (NJPW) debut on June 9, 2018 as part of NJPW’s Dominion 6.9 in Osaka-jo Hall show. Mysterio teamed up with Jushin Thunder Liger and Hiroshi Tanahashi, losing to the Bullet Club team of Cody, Marty Scurll and Adam Page.

On June 3, 2018, Mysterio returned to Lucha Libre AAA Worldwide (AAA) at Verano de Escándalo, competing in a three-way match for the AAA Mega Championship against Rey Wegner and Jeff Jarrett, with Jarrett winning.

On January 28, 2018, at the Royal Rumble, Mysterio made a one night appearance, entering as a surprise entrant at number 27 in the Royal Rumble match, eliminating Adam Cole before later being eliminated by Finn Bálor. At the Greatest Royal Rumble event on April 27, Mysterio participated in the 50-man Royal Rumble match, but was eliminated by Baron Corbin. On June 26, Mysterio was revealed as one of the pre-order bonus character for WWE 2K19. On September 19, it was confirmed Mysterio had signed a two-year contract with WWE.

On October 16, on the 1000th episode of SmackDown, Mysterio competed in his first singles match with the company since April 2014, where he defeated Shinsuke Nakamura to qualify for the WWE World Cup tournament. During the tournament at Crown Jewel, Mysterio defeated Randy Orton in the first round, but was attacked by Orton after the match. Later in the night, Mysterio lost to The Miz in the semi-finals. On the November 6 episode of SmackDown Live, Mysterio defeated Andrade “Cien” Almas to qualify for Team SmackDown in a 5-on-5 Survivor Series elimination match at Survivor Series. At the event, Mysterio eliminated Finn Bálor before being eliminated by Braun Strowman, and Team SmackDown ultimately lost to Team Raw. Two nights later on SmackDown Live, Mysterio was attacked by Randy Orton, as well as he ripped Mysterio’s mask off of his face. The two fought the following week, with Orton getting the upper-hand. At TLC: Tables, Ladders & Chairs, Mysterio defeated Orton in a Chairs match, ending their feud. On January 27, 2019, at the Royal Rumble, Mysterio entered the Royal Rumble match at number 25, but was eliminated by Orton.