The 1989–90 Iowa State Cyclones men's basketball team represented Iowa State University during the 1989–90 NCAA Division I men's basketball season. The Cyclones were coached by Johnny Orr, who was in his 10th season. They played their home games at Hilton Coliseum in Ames, Iowa. They finished the season 10–18, 4–10 in Big Eight play to finish in sixth place. They lost to third-seeded Kansas in the 1990 Big Eight conference tournament quarterfinals. Games were televised by ESPN, Raycom Sports, and the Cyclone Television Network.