The 2009–10 NCAA Division I men's basketball season began on November 9, 2009, and ended with the 2010 NCAA Division I men's basketball tournament's championship game on April 5, 2010, on the Lucas Oil Stadium in Indianapolis. The opening round occurred on Tuesday, March 16, 2010, followed by first and second rounds on Thursday through Sunday, March 18–21, 2010. Regional games were played on Thursday through Sunday, March 25–28, 2010, with the Final Four played on Saturday and Monday, April 3 and 5, 2010.

• The Duke Blue Devils and head coach Mike Krzyzewski won their fourth national championship, defeating upstart Butler 61–59 behind their "big three" of Jon Scheyer, Kyle Singler and Nolan Smith. The game was played in Butler's home town of Indianapolis.
• Krzyzewski became the third coach in NCAA history to win four championships, joining John Wooden (10) and Adolph Rupp (4).^[1]
• Kentucky became the first college team to reach the 2000 win mark by defeating Drexel 88–44 on December 21.^[2] North Carolina became the second with a win over Miami on March 2. Kansas became the third with a win over Texas Tech on March 11.
• Arkansas sophomore guard Rotnei Clarke set an SEC record by hitting 13 three-pointers in a game in the Razorbacks' November 13 season opener against Alcorn State. Clarke connected on 13 of 17 three-pointers and finished the game with 51 points.^[3] Clarke's 51 points was an Arkansas school record, while his 13 threes was good for fifth in NCAA history.
• Prior to the season the NCAA announced that Memphis would serve three years' probation and would vacate their record-setting 38-win 2007–08 season due to a fraudulent SAT score by star Derrick Rose and extra benefits given to Rose's brother under then-coach John Calipari.^[4] Memphis appealed the decision. The NCAA rejected the appeal during the NCAA tournament.^[5]
• Binghamton University dismissed six players on September 25, following the arraignment of Emanuel "Tiki" Mayben on charges of cocaine distribution.^[6] The move left Binghamton with only seven scholarship players for the 2009–10 season and included the dismissal of star guard D.J. Rivera. Coach Kevin Broadus was placed on administrative leave and assistant Mark Macon served as interim coach.
• The preseason AP All-American team was named on November 2. Luke Harangody of Notre Dame (57 votes), Cole Aldrich (49) and Sherron Collins (39) of Kansas, Patrick Patterson of Kentucky (35) and Kyle Singler of Duke (30) were tabbed.^[7]
• Utah Valley gained full Division I status after a seven-year provisional period where they played a D1 schedule. This move was the first time that a school had moved to D1 directly from the NJCAA.^[8] Other schools to officially gain Division I status include Kennesaw State, NJIT and North Florida.
• The Great West Conference began league play in 2009–10 as the 32nd Division I conference.^[9]
• Notre Dame forward Luke Harangody surpassed both the 2000-point and 1000-rebound marks during the season, becoming the first Fighting Irish player to do so.
• Mercer guard James Florence, South Carolina guard Devan Downey, Maryland guard Greivis Vásquez, San Francisco forward Dior Lowhorn, Morgan State guard Reggie Holmes, Western Michigan guard David Kool, West Virginia forward Da'Sean Butler, Villanova guard Scottie Reynolds, Cornell forward Ryan Wittman and Duke guard Jon Scheyer surpassed the 2,000 point mark during the season.
• Syracuse coach Jim Boeheim became the eighth Division I coach to win 800 games when the Orange defeated Albany 75–43 on November 9.^[10]
• Tom Penders became the eighth head coach in NCAA history to lead four different schools to the NCAA Tournament when he coached the Houston Cougars to the Conference USA tournament title. Penders had previously led Rhode Island, Texas and George Washington to NCAA tournament berths.
• In November, Evan Turner became the 34th player to record multiple triple doubles in a season.^[11] Over the course of the 2009–10 Big Ten season, he became the first player to finish in the top two in average points (1st, 20.4), rebounds (2nd, 9.2) and assists (2nd, 6.0) in Big Ten Conference history.^[12][13] Along the way, he broke and rebroke Big Ten records for single-season (7) and career (10) Player of the week awards.^[14][15][16]
• On February 22, Cole Aldrich was named the men's college basketball Academic All-American of the year.^[17]
• On February 24, Mississippi State's Jarvis Varnado became the NCAA's all-time leading shot-blocker.^[18]
• On February 27, a contest between then-no. 4 Syracuse and then-no. 8 Villanova set the NCAA on-campus basketball attendance record, with 34,616 spectators packing the Carrier Dome.^[19] The Wildcats fell to the Orange, 95–77.^[19]
• The rise and fall of Texas. Ranked in the top three from the beginning of the season until mid-January, including two weeks at #1, they were considered national title contenders.^[20] But they fell out of the top 25 less than two months later, lost two starters (Doğuş Balbay and Varez Ward) to season-ending injuries, and lost in the opening round of the NCAA tournament.
• On April 1, Deon Thompson of North Carolina appeared in the NIT Championship game, giving him 152 career game appearances.^[21] This set the NCAA all-time career games played mark, formerly held by Wayne Turner of Kentucky and Walter Hodge of Florida.^[21]
• Third-year coach Tommy Amaker leads Harvard to its most wins in school history (21) behind the play of rare Harvard NBA player Jeremy Lin.^[22]

Beginning in 2009–10, the following rules changes were implemented:

• The NCAA reduced the amount of time that college underclassmen can test the waters for the NBA draft and still retain their college eligibility. As of this season, players have until early May (rather than mid-June) to decide to return.^[23]
• Secondary defenders must now establish their position outside of the zone between the backboard and the front of the rim to draw a charge.^[24]
• If a player is injured and unable to shoot his own foul shots, the replacement shooter must be chosen from the players currently on the court.^[24]
• Instant replay may now be used to determine flagrant fouls.^[24]

These schools joined new conferences for the 2009–10 season.