The 1989–90 UNLV Runnin' Rebels basketball team represented the University of Nevada Las Vegas in the 1989–90 NCAA Division I men's basketball season. They were led by 17th-year head coach Jerry Tarkanian. The team played its home games in the Thomas & Mack Center as a member of the Big West Conference. They finished the season 35–5, 16–2 in Big West play to win the regular season championship. They defeated Cal State Fullerton, Pacific, and Long Beach State to win the Big West tournament championship. As a result, the received the conference's automatic bid to the NCAA tournament as the No. 1 seed in the West region. They defeated Arkansas–Little Rock, Ohio State, Ball State, and Loyola Marymount to advance to the school's second Final Four in 4 years. In the Final Four, they defeated Georgia Tech to advance to the championship game where they defeated Duke for the school's only national championship.