The 2008 Phillips 66 Big 12 Men's Basketball Championship was the 2008 edition of the Big 12 Conference's championship tournament held at the Sprint Center in Kansas City from March 13 until March 16, 2008. It was the 12th Big 12 tournament in the series. Texas and Kansas shared the regular season title, with Texas receiving the top seed in the tournament due to its win over Kansas earlier in the season. The top four seeds, including the two regular season champs, Oklahoma, and Kansas State automatically advanced to the quarterfinal round.