DuPree was born and reared in Monroe, Louisiana. He played high school football at Richardson High School in West Monroe, Louisiana, winning the school’s division State Championship two of the 3 years he played while serving as a co-captain his senior year.

DuPree played collegiately at Michigan State University. He is recognized as the greatest tight end in Michigan State history,[2] even though he had few opportunities to prove his true worth in the Spartans run-oriented offense. DuPree led his team in receiving as a junior in 1971 (25 catches, 414 yards, three touchdowns) and as a senior was the team’s co-captain in 1972 (23 catches for 406 yards). Nevertheless, that was enough to get him noticed for All-America honors.

DuPree was the last tight end to lead Michigan State University in receiving. He ended his collegiate career with 69 receptions.

DuPree was drafted by the Dallas Cowboys in the first round (20th overall) of the 1973 NFL Draft. As a rookie he led the team in receiving yards (392) and was second in receiving touchdowns.

Known as a superb blocker and pass receiver, DuPree was one of the top tight ends of his era.

He caught 267 passes for 3,565 yards and 42 touchdowns. He also rushed for 178 yards and a touchdown on 28 carries.

Dupree was selected to three consecutive Pro Bowls,(1976–1978), and assisted his team to a 27–10 victory over the Denver Broncos in Super Bowl XII, as the top receiver of the game (four catches for 66 yards). He also played in Super Bowl X and scored a touchdown in Super Bowl XIII; in both games the Cowboys lost against the Pittsburgh Steelers.

Even though tight ends during his era were expected to block more than feature their receiving skills, his 41 career touchdown receptions team mark, was broken until 2012 by Jason Witten.

The durable DuPree never missed a game in his 11 seasons in the league and was part of the franchise’s legacy of Pro Bowl tight ends that includes: Jim Doran, Dick Bielski, Lee Folkins, Mike Ditka, Doug Cosbie, Jay Novacek and Jason Witten. He was also a Cowboys co-captain and recognized as the team’s NFL Man of the Year.

More recently, he has become involved in many charities, including the Shriner’s, as well as other inner city youth groups. He is an active participant in most NFL Alumni Children’s Charity events. He was elected to the Blue–Gray Football Classic Hall of Fame, the Louisiana Sports Hall of Fame and the Texas State African-American Sports Hall of Fame. He is an active member of the Board of Trustees of Meals on Wheels of Collin County.