Mingo was born in Belle Glade, Florida. He attended West Monroe High School in West Monroe, Louisiana, where he was a letterman in football and track. He played football for the West Monroe Rebels team under head coach Don Shows. As a junior, he tallied 55 tackles to go with six sacks and 12 tackles for loss, leading this to be named All-State in Class 5A. As a senior in 2008, he was a 5A first-team All-state selection, after recording 59 tackles to go with seven tackles for loss and four sacks in helping lead West Monroe High School to the state championship game. He also added four forced fumbles and recovered seven fumbles. He played in the 2009 U.S. Army All-American Bowl.

Mingo attended Louisiana State University, and played for coach Les Miles’s LSU Tigers football team from 2009 to 2012. He was redshirted in 2009. As a redshirt freshman in 2010, he started one of 13 games, recording 35 tackles and 3.5 sacks. As a sophomore in 2011, Mingo was a Second Team All-SEC selection after recording 47 tackles and 8 sacks. In 2011, he contributed to LSU’s successful SEC Championship season. As a junior in 2012, he played in all 13 games with 10 starts, and earned Second Team All-SEC honors after recording 38 tackles, 8.5 tackles for a loss, 4.5 quarterback sacks, and a team-high 12 quarterback hurries.

On January 7, 2013, Mingo announced he would forego his senior season and enter the 2013 NFL Draft. He was one of 10 LSU Tiger underclassmen to declare for the draft that year.

Mingo was drafted by the Cleveland Browns in the first round with the sixth overall pick in the 2013 NFL Draft. He was the third defensive end to be selected in the draft, after Dion Jordan and Ezekiel Ansah.

On July 21, 2013, the Cleveland Browns signed Mingo to a four-year, $16.34 million contract that included a signing bonus of $10.26 million.

Mingo was immediately moved to outside linebacker by defensive coordinator Ray Horton and competed against Jabaal Sheard for a starting role throughout training camp. On August 15, 2013, Mingo suffered a bruised lung during the Browns’ 24-6 win against the Detroit Lions during their second preseason game. Mingo was hospitalized and missed the last two games of the preseason. Head coach Rob Chudzinski named Mingo a backup outside linebacker, behind Jabaal Sheard and Paul Kruger, to begin the regular season.

On September 15, 2013, Mingo made his professional regular season debut after missing the season-opener due to a bruised lung and recorded two solo tackles, one pass deflection, and made his first career sack during their 14-6 loss at the Baltimore Ravens in Week 2. Mingo made his first career sack on Ravens’ quarterback Joe Flacco for a nine-yard loss during the first quarter. On September 29, 2013, Mingo earned his first career start in place of Jabaal Sheard who was inactive due to a knee injury. In Week 13, he collected a season-high five combined tackles during a 32-28 loss against the Jacksonville Jaguars. On December 30, 2013, the Cleveland Browns fired head coach Rob Chudzinski after they finished the season with a 4-12 record. He finished his rookie season in 2013 with 42 combined tackles (39 solo), a career-high five sacks, and four pass deflections in 15 games and three starts.

Mingo entered training camp as a backup outside linebacker in his first season under defensive coordinator Jim O’Neil. Head coach Mike Pettine named Mingo and Paul Kruger the starting outside linebackers to begin the regular season. They started alongside inside linebackers Craig Robertson and Karlos Dansby. Mingo was inactive for the Browns’ Week 2 victory against the New Orleans Saints due to a shoulder injury. Mingo’s shoulder injury was discovered to be a torn labrum, but he opted to wear a harness and play through the injury. On December 14, 2014, Mingo collected a season-high eight combined tackles during a 30-0 loss against the Cincinnati Bengals in Week 15. He finished the season with 42 combined tackles (26 solo), three pass deflections, and two sacks in 15 games and 11 starts.

Mingo entered training camp slated as the starting strongside linebacker after Jabaal Sheard departed during free agency. On August 6, 2015, Mingo underwent arthroscopic surgery on a torn meniscus and was expected to miss 2–4 weeks. Head coach Mike Pettine retained Mingo and Paul Kruger as the starting outside linebackers to begin the regular season. Mingo was demoted to being a backup outside linebacker after Armonty Bryant was given his starting role. In Week 3, he collected a season-high four combined tackles during a 27-20 loss against the Oakland Raiders. On October 18, 2015, Mingo made one tackle, broke up one pass deflection, and made his first career interception during a 26-23 loss against the Denver Broncos in Week 6. Mingo intercepted a pass by Broncos’ quarterback Peyton Manning, that was initially intended for wide receiver Demaryius Thomas, and returned it for a seven-yard return in overtime. He finished the 2015 NFL season with 24 combined tackles (15 solo), four pass deflections, and one interception in 16 games and two starts.

On January 4, 2016, the Cleveland Browns fired head coach Mike Pettine and general manager Ray Farmer after they finished the season with a 3-13 record. On May 2, 2016, the Cleveland Browns decided not to pick up his fifth year option. Defensive coordinator Ray Horton retained the 3-4 base defense and held a competition to name starting outside linebackers between Mingo, Paul Kruger. Nate Orchard, Joe Schobert, and Emmanuel Ogbah.

On August 25, 2016, the Cleveland Browns traded Mingo to the New England Patriots and received a fifth-round pick (175th overall) in the 2017 NFL Draft in exchange. Head coach Bill Belichick named Mingo the fourth outside linebacker on the Patriots’ depth chart to start the regular season. He was listed behind Jamie Collins, Jonathan Freeny, and Shea McClellin.

In Week 6, Mingo collected a season-high two solo tackles during a 35-17 victory against the Cincinnati Bengals. Mingo was limited to 11 combined tackles (nine solo) in his only season with the Patriots, but appeared in all 16 games with zero starts. The New England Patriots finished first in the AFC East with a 14–2 record and earned a first round bye. On January 14, 2017, Mingo appeared in his first career playoff game as the Patriots defeated the Houston Texans 34–16 in the AFC Divisional Round. The following week, they defeated the Pittsburgh Steelers 36–17 in the AFC Championship Game. On February 5, 2017, Mingo appeared in Super Bowl LI and recorded two solo tackles as the Patriots defeated the Atlanta Falcons 34–28. Mingo appeared exclusively on special teams during the game and recorded both his tackles while covering punt returns.

On March 9, 2017, the Indianapolis Colts signed Mingo to a one-year, $2 million contract that includes a signing bonus of $500,000. Mingo reunited with teammate Jabaal Sheard for the third time. They were teammates on the New England Patriots and Cleveland Browns.

Mingo competed against John Simon and Jabaal Sheard to be the starting strongside linebacker. Head coach Chuck Pagano named Mingo the backup strongside linebacker, behind John Simon, to begin the regular season. In Week 16, he collected a season-high eight solo tackles and made one sack during a 23-16 loss at the Baltimore Ravens. On December 31, 2017, the Indianapolis Colts fired head coach Chuck Pagano after finishing the season with a 4-12 record. Mingo finished his lone season with the Indianapolis Colts with 47 combined tackles (35 solo), two pass deflections, and two sacks in 16 games and six starts.

On March 16, 2018, the Seattle Seahawks signed Mingo to a two-year, $6.80 million contract that includes $3.20 million guaranteed and a signing bonus of $2.20 million.

On August 31, 2019, the Seahawks traded Mingo along with outside linebacker Jacob Martin and a 2020 third-round pick to the Houston Texans in exchange for Jadeveon Clowney.

On April 3, 2020, the Chicago Bears signed Mingo to a one-year, $1.187 million contract.