The 1981 Big Eight men's basketball tournament was held March 3–5 at a combination of on-campus gymnasiums and Kemper Arena in Kansas City, Missouri.^[2]

In a rematch of the 1980 final (won by KSU), Kansas upset rivals Kansas State in the championship game, 80–68, to win their first Big Eight men's basketball tournament.

The Jayhawks, in turn, received an automatic bid to the 1981 NCAA tournament. They were joined in the tournament by fellow Big Eight members Missouri and Kansas State, who earned at-large bids.

All eight of the conference's members participated in the tournament field. They were seeded based on regular season conference records, with all teams placed and paired in the initial quarterfinal round.

All first-round games were played on the home court of the higher-seeded team. The semifinals and championship game, in turn, were played at a neutral site at Kemper Arena in Kansas City, Missouri.