The 2005–06 NCAA Division I men's basketball season began on November 6, 2005, progressed through the regular season and conference tournaments and concluded with the 2006 NCAA Division I men's basketball tournament championship game on April 3, 2006, at the RCA Dome in Indianapolis, Indiana. The Florida Gators won their first NCAA national championship with a 73–56 victory over the UCLA Bruins. This was the last Final Four site at the RCA Dome. The Final Four will return to the city of Indianapolis, but will be held at Lucas Oil Stadium.

The 2006 NCAA Division I men's basketball tournament involved 65 teams playing in a single-elimination tournament to determine the national champion of men's NCAA Division I college basketball as a culmination of the 2005–06 basketball season. It began on March 14, 2006, and concluded with the championship game on April 3 at the RCA Dome in Indianapolis, Indiana.