Joe Greene is a former professional football player. Born and raised in Temple, Texas, Greene attended North Texas State University (now University of North Texas), where he earned consensus All-America honors as a senior playing for the North Texas State Mean Green football team.

He was drafted by the Steelers fourth overall in the 1969 NFL Draft and made an immediate impact with the team, as he was named the NFL's Defensive Rookie of the Year. Greene was a defensive tackle for the NFL's Pittsburgh Steelers from 1969 to 1981. A recipient of two NFL Defensive Player of the Year awards, five first-team All-Pro selections, and ten Pro Bowl appearances, Greene is widely considered to be one of the greatest defensive linemen to ever play in the NFL. He was noted for his leadership, competitiveness, and intimidating style of play. Greene is credited with providing the foundation upon which Steelers coach Chuck Noll turned the dismal franchise into a sports dynasty. He was the centerpiece of the "Steel Curtain" defense that led Pittsburgh to four Super Bowl championships in a six-year span. Former teammate Andy Russell called Greene "unquestionably the NFL's best player in the seventies."

Greene is a member of the Pro Football Hall of Fame and the College Football Hall of Fame, and his number 75 jersey is one of only two retired by the Steelers. In 2018 Greene set up the Agnes Lucille Craft Greene Memorial Scholarship in honor of his late wife. The scholarships are presented annually to students from Texas, whose parents have battled cancer.