Dent grew up in Sylvania, Georgia, and Hialeah, Florida, graduating from Hialeah High School. The sixth overall pick in the 1970 MLB draft out of high school, by the age of 21 he was playing shortstop for the Chicago White Sox, wearing uniform number 30. The pressure of succeeding Luis Aparicio at the position was problematic, and the White Sox traded him to the Yankees in early April 1977 for Oscar Gamble, LaMarr Hoyt, a minor leaguer, and $200,000. The Yankees gave him uniform number 20 and they went on to win the World Series that year.

In 1978, Dent is widely remembered for hitting a three-run home run that gave the Yankees a 3–2 lead in the AL East division tie-breaker game against the Boston Red Sox. This was all the more remarkable because Dent was not a power hitter; his seventh-inning home run was one of only 40 he hit in his entire 12-year career. Further, Dent occupied the ninth spot in the batting order, not generally considered a power slot, and did it with a bat borrowed from center fielder Mickey Rivers. The Yankees went on to win the game 5–4 for the division title; Boston was left out of the playoffs, after squandering one of the largest July leads in major league history. A generation of Red Sox fans have since referred to him as “Bucky Fucking Dent.”

In 1979, Dent posed for a pin-up poster. That year he also appeared in the TV movie Dallas Cowboys Cheerleaders, portraying a wide receiver who was the love interest of one of the cheerleaders. He also appeared in the September 1983 issue of Playgirl magazine wearing a swimsuit.

On the Rangers, his uniform number was 7. Dent returned to the Yankees briefly in 1984 (but never played a game) before finishing his career that season with the Kansas City Royals, wearing uniform number 21. He spent his entire 12-year playing career in the American League, with a .247 batting average and 423 RBI.

After retiring as a player, Dent managed in the Yankees’ minor-league system, notably with the Columbus Clippers. He served the Yankees as manager of the big-league club for portions of two seasons, compiling an 18–22 record in 1989 and an 18–31 record in 1990. Owner George Steinbrenner hired Dent only as a stopgap, and did not believe he could lead the Yankees back to postseason play. He intended to replace Dent with Billy Martin at the earliest opportunity in 1990, but those plans were brought undone when Martin died in a car accident on Christmas Day in 1989.

In 1989 Dent opened a baseball school at Delray Beach, Florida, which featured a miniature version of Fenway Park. Although Dent had his greatest moment as a player at Fenway Park, his worst moment also came at Fenway Park when he was fired as manager of the Yankees. Dan Shaughnessy of The Boston Globe criticized Steinbrenner for firing Dent in Boston and said he should “have waited until the Yankees got to Baltimore” to fire Dent. He said that “if Dent had been fired in Seattle or Milwaukee, this would have been just another event in an endless line of George’s jettisons. But it happened in Boston and the nightly news had its hook”. He also said that “the firing was only special because…it’s the first time a Yankee manager…was purged on the ancient Indian burial grounds of the Back Bay”. However, Bill Pennington called the firing of Dent “merciless.”

From 1991 to 1994, Dent served on the coaching staff of the St. Louis Cardinals under manager Joe Torre, moving to the coaching staff of the Texas Rangers from 1995 to 2001.

In 2002, Dent served as the manager for the Omaha Royals, the Triple A affiliate of the Kansas City Royals.

In 2003, when the Green Monster seats were added to Fenway Park, Dent attended the first game and sat in a Green Monster seat that was very near to where his 1978 home run landed. No animosity was displayed towards him by Red Sox fans at that game, who were all cordial to him.

In November 2005, Dent became the bench coach for the Cincinnati Reds. The Cincinnati Reds released Dent on July 3, 2007; just a few days after releasing manager Jerry Narron. At the time, the Reds had the worst record in Major League Baseball.

In 2014, Dent made a cameo as a father in the feature film Walt Before Mickey.

His late wife, Marianne, died on October 22, 2015; they were the parents of twin children, Cody and Caitlin. He also has two children with his ex-wife, Karen “Stormie” Neale, Scott and Stacy.

He now lives in Lake Worth, Florida with his wife, Angie Wildstein, his long time business partner, with whom he eloped in November 2019.