The 2003 Atlantic Coast Conference Men's Basketball Tournament took place from March 13-16, 2003 in Greensboro, North Carolina at the Greensboro Coliseum. The 2003 edition marked the 50th ACC tournament in history. Duke won the tournament for the fifth straight time. They defeated NC State in the championship game for the second year in a row. Duke's Daniel Ewing won the tournament's Most Valuable Player award.