The 2019 Phillips 66 Big 12 men's basketball tournament was the postseason men's basketball tournament for the Big 12 Conference. It was played from March 13 to 16, in Kansas City, Missouri at the Sprint Center. No. 5 seed Iowa State defeated Kansas 78–66 to win the championship and receive the Big 12’s automatic bid to the 2019 NCAA tournament. It was Iowa State's fourth Big 12 title in the last six years. They also became the first team lower than a four seed to win the tournament.