The 2003 Atlantic Sun men's basketball tournament was held March 6–8 at the GSU Sports Arena at Georgia State University in Atlanta, Georgia.
[1] Troy State defeated UCF in the championship game, 80–69, to win their first Atlantic Sun men's basketball tournament.
The Trojans, therefore, received the Atlantic Sun's automatic bid to the 2003 NCAA tournament, their first appearance in the Division I tournament.
The Atlantic Sun's membership remained fixed at twelve, so no changes to the format were required.
These eight teams were seeded based on regular season conference records.