The 2008–09 NCAA Division I men's basketball season began on November 10, 2008, and ended with the 2009 NCAA Division I men's basketball tournament's championship game on April 6, 2009, at Ford Field in Detroit, Michigan. The season saw six different teams achieve the AP #1 ranking during the year (just one shy of the NCAA record). Oklahoma sophomore Blake Griffin was the dominant individual performer, sweeping National Player of the Year honors. The season began with North Carolina becoming the first unanimous preseason #1 team, and ended with the Tar Heels dominating the NCAA tournament en route to their fifth NCAA title. UNC won its six NCAA tournament games by double digits, and by an average of 19.8 points per game. Junior Wayne Ellington was named Final Four Most Outstanding Player.

Season headlines

Major rule changes

Beginning in 2008–2009, the following rules changes were implemented:

Season outlook

Pre-season polls

The top 25 from the AP and ESPN/USA Today Coaches Polls, October 31, 2008.

Conference membership changes

These schools joined new conferences for the 2008–09 season.

Regular season

Early-season tournaments

Conferences

Conference winners and tournaments

Thirty conference seasons concluded with a single-elimination tournament. The teams in each conference that won their regular-season conference title received the number one seed in each tournament. Conference tournament winners received an automatic bid to the 2009 NCAA Division I men's basketball tournament. The Ivy League was the only NCAA Division I conference that did not hold a conference tournament, instead sending its regular-season champion, Cornell, to the NCAA tournament.

Conference standings

Division I independents

Fifteen schools played as Division I independents. However, only, Longwood, Savannah State, and were considered full NCAA Division I schools, as the rest were still in a transition phase from NCAA Division II. David Holston of Chicago State was named Independent Player of the Year.

Informal championships

Villanova finished with a 4–0 record in head-to-head competition among the Philadelphia Big 5.

Statistical leaders

Source for additional stats categories

Post-season tournaments

NCAA tournament

The NCAA Tournament tipped off on March 18, 2009, with the opening round game in Dayton, Ohio, and concluded on April 6 at the Ford Field in Detroit, Michigan. Of the 65 teams that were invited to participate, 31 were automatic bids while 34 were at-large bids. The 34 at-large teams came from 8 conferences, with the Big East, ACC and Big Ten each receiving seven bids. The Big 12 and Pac-10 each received six bids. The SEC and Atlantic 10 each received three bids. This season also marked the first time that three teams from the same conference were selected as #1 seeds (Louisville, Pittsburgh and Connecticut). North Carolina tore through the tournament, winning each game by 12 or more points and beating Michigan State in the Final 89–72 behind an NCAA-record 55 first-half points to win its fifth National championship. Ty Lawson recorded a record 8 steals, while Wayne Ellington was named tournament Most Outstanding Player.

Final Four – Ford Field, Detroit, Michigan

National Invitation tournament

After the NCAA Tournament field was announced, the National Invitation Tournament invited 32 teams to participate. Five teams were automatic qualifiers for winning their conference regular-season championships, while the remaining 27 bids were named from an at-large pool. Notable entrants included Kentucky, who broke a 17-year NCAA tournament appearance streak by missing the field, as well as preseason top ten team Notre Dame and 2008 Regional Finalist Davidson. Penn State defeated Baylor 69–63 in the Final on April 2. The Nittany Lions' Jamelle Cornley was named tournament Most Outstanding Player.

NIT Semifinals and Final

Played at Madison Square Garden in New York City on March 31 and April 2

College Basketball Invitational

The second College Basketball Invitational (CBI) Tournament was held beginning March 17 and ended with a best-of-three final, ending March 30. Oregon State defeated UTEP 2–1 in the final series to win the title. Oregon State's Roeland Schaftenaar was named tournament MVP.

CollegeInsider.com tournament

The inaugural CollegeInsider.com Postseason Tournament was held beginning March 17 and ended with a championship game on March 30. This tournament places an emphasis on selecting successful teams from "mid-major" conferences who were left out of the NCAA Tournament and NIT. Old Dominion defeated Bradley 66–62 to win the first CIT championship in Peoria, Illinois. The Monarchs' Frank Hassell was named tournament MVP.

Award winners

Consensus All-American teams

Major player of the year awards

Major freshman of the year awards

Major coach of the year awards

Other major awards

Coaching changes

A number of teams changed coaches throughout the season and after the season ended.