The 1999–2000 Iowa State Cyclones men's basketball team represents Iowa State University during the 1999–2000 NCAA Division I men's basketball season. The Cyclones were coached by Larry Eustachy, who was in his 2nd season. They played their home games at Hilton Coliseum in Ames, Iowa and competed in the Big 12 Conference. The captains were Stevie Johnson and Michael Nurse.