1990–91 Princeton Tigers men's basketball team

The 1990–91 Princeton Tigers men's basketball team represented Princeton University in intercollegiate college basketball during the 1990–91 NCAA Division I men's basketball season. The head coach was Pete Carril and the team captain was Kit Mueller. The team played its home games in the Jadwin Gymnasium on the University campus in Princeton, New Jersey. The team was the undefeated champion of the Ivy League, which earned them an invitation to the 64-team 1991 NCAA Men's Division I Basketball Tournament where they were seeded eighth in the East Region.

The team posted a 24–3 overall record and a 14–0 conference record using the Princeton offense. When the team beat Yale 55–27 on January 11, 1991, it established a new National Collegiate Athletic Association Division I record for fewest points allowed (since 1986), breaking its own record set the prior year. The record would last until March 2, 1992. On February 8, 1991, against Cornell, Sean Jackson made all five of his three-point field goal attempts, which tied the Ivy League single-game record for most made without a miss set three years earlier by Princeton Tigers Dave Orlandini and Bob Scrabis. These stood as unsurpassed as the Ivy League record until future Princeton Tigers head coach Sydney Johnson made all six for Princeton on February 28, 1997. In a March 15, 1991 NCAA Men's Division I Basketball Tournament East Regional first round game at the Carrier Dome in Syracuse, New York, against the Villanova Wildcats, they lost by a 50–48 margin. The Tigers led 30–25 at halftime, but lost on a shot in the final second of regulation play. Princeton's number eight seed was a record for the highest seed by an Ivy League school at the time.