The 1985 NCAA Men's Division I Basketball Tournament involved 64 schools playing in single-elimination play to determine the national champion of men's NCAA Division I college basketball. This was the first year the field was expanded to 64 teams, from 53 in the previous year's tournament. It began on March 7, 1985, and ended with the championship game on April 1 in Lexington, Kentucky. A total of 63 games were played.
Eight-seed Villanova, coached by Rollie Massimino, won the national title with a 66–64 victory in the final game over Georgetown, coached by John Thompson. Ed Pinckney of Villanova was named the tournament's Most Outstanding Player. The game is often cited among the greatest upsets in all of sports. This Villanova team remains the lowest-seeded team to win the tournament. The game is also notable as the last played without a shot clock.
This year's Final Four saw an unprecedented and unmatched three teams from the same conference, with Big East members Villanova and Georgetown joined by St. John's. The only "interloper" in the Big East party was Memphis State, then of the Metro Conference. (Memphis State's 1985 Final Four appearance was vacated due to using ineligible players, as were all tournament appearances from 1982-1986.)
This was also the first year that one of the regionals was named "Southeast," replacing "Mideast." This name was used until 1998, when the regional was renamed "South."