The 2004 NCAA Division I men's basketball tournament involved 65 schools playing in single-elimination play to determine the national champion of men's NCAA Division I college basketball. It began on March 16, 2004, and ended with the championship game on April 5 at the Alamodome in San Antonio, Texas. A total of 64 games were played. The NCAA named, for the first time, the four tournament regions after regional site host cities instead of the "East", "Midwest", "South", and "West" designations. It was also the first year that the matchups for the national semifinals were determined at least in part by the overall seeding of the top team in each regional. The top four teams in the tournament were Kentucky, Duke, Stanford, and Saint Joseph's. Had all of those teams advanced to the Final Four, Kentucky would have played Saint Joseph's and Duke would have played Stanford in the semifinal games. Of those teams, only Duke advanced to the Final Four. They were joined by Connecticut, making their first appearance since defeating Duke for the national championship in 1999, Oklahoma State, making their first appearance since 1995, and Georgia Tech, making their first appearance since 1990. Connecticut defeated Georgia Tech 82–73 to win their second national championship in as many tries. Emeka Okafor of Connecticut was named the tournament's Most Outstanding Player. As they had in 1999, Connecticut won their regional championship in Phoenix, Arizona. Two of the tournament's top seeds failed to make it past the opening weekend. Kentucky, number one seed of the St. Louis region, and Stanford, #1 seed of the Phoenix region, both were defeated. Incidentally, both teams were defeated by schools from Alabama, as Kentucky fell to UAB while Stanford lost to Alabama. Due to their strong 2003–04 season, Gonzaga achieved its highest NCAA tournament seed until 2013 by receiving the #2 seed in the St. Louis region. Gonzaga would receive a #1 seed in the 2013 tournament. The team failed to advance beyond the first weekend of the tournament, however.

Schedule and venues

The following are the sites that were selected to host each round of the 2004 tournament: Opening Round First and Second Rounds Regional semifinals and finals (Sweet Sixteen and Elite Eight) National semifinals and championship (Final Four and championship)

Qualifying teams

Automatic bids

The following teams were automatic qualifiers for the 2004 NCAA field by virtue of winning their conference's tournament (except for the Ivy League, whose regular-season champion received the automatic bid).

Listed by region and seeding

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Bids by conference

Record by conference

• Florida A&M University won the Opening Round game. The America East, Atlantic Sun, Big Sky, Big South, CAA, Horizon League, Mid-Continent, Ivy, MAC, MEAC, Northeast, Ohio Valley, Patriot, SoCon, Southland, SWAC, and Sun Belt conferences all went 0–1. The columns R32, S16, E8, F4, and CG respectively stand for the Round of 32, Sweet Sixteen, Elite Eight, Final Four, and championship Game.

Final Four

At Alamodome, San Antonio, Texas

National semifinals

National Championship Game

Bracket

Opening Round game – Dayton, Ohio

Winner advances to 16th seed in St. Louis Regional vs. (1) Kentucky.

East Rutherford Regional

St. Louis Regional

Atlanta Regional

Phoenix Regional

Final Four – San Antonio, Texas

Game summaries

Final four

National Championship

Announcers

Greg Gumbel once again served as the studio host, joined by analysts Clark Kellogg and Seth Davis.