The 1991 Atlantic Coast Conference men's basketball tournament took place in Charlotte, North Carolina, at the second Charlotte Coliseum. North Carolina won the tournament, defeating Duke, 96–74, in the championship game. Rick Fox of North Carolina was named tournament MVP. did not participate in the tournament because the program was on probation. Top seed Duke received a first-round bye into the semifinals. The only other times an ACC team opted out of the tournament were in 1961, Syracuse in 2015, and Louisville in 2016 for similar reasons.

Bracket

AP rankings at time of tournament