The 2003 National Invitation Tournament was the 2003 edition of the annual NCAA college basketball competition. This was the last NIT to include a third-place game until 2021.
During the following season, St. John's center Abe Keita revealed that a member of the team's staff had paid him nearly $300 a month for the past four seasons. As a result, St. John's took various actions, including vacating 43 wins in which Keita participated, among which were the team's victories and eventual championship in the 2003 NIT. St. John's became the third team in the history of the NIT to be forced to vacate its standing in the tournament. Marcus Hatten's tournament Most Valuable Player award also was vacated.
Below is a list of the 40 teams selected for the tournament.
Below are the four first round brackets, along with the four-team championship bracket.
NOTE: St. John's later vacated its tournament wins and title championship due to an ineligible player.