The 2015–16 NCAA Division I men's basketball season began on November 13. The first tournament was the 2K Sports Classic and ended with the Final Four in Houston April 2–4. Practices officially began on October 2.

The following rule changes were proposed by the NCAA Men's Rules Committee for the 2015–16 season,^[1][2] and officially approved by the NCAA Men's Playing Rules Oversight Panel:^[3]

• Reducing the shot clock from 35 to 30 seconds (same as the women's game).
• Providing offensive players the same verticality protections as defensive players.
• Extending the restricted-area arc from 3 feet to 4 feet from the basket.
• Reducing the number of team timeouts from 5 to 4, with a limit of no more than 3 timeouts in the second half.
• Ending the practice of coaches calling timeouts from the bench in live-ball situations.
• Tightening the 10-second backcourt rule, under which the offensive team has 10 seconds to advance the ball from the backcourt to the frontcourt. The following situations, all of which resulted in a reset of the 10-second count under previous rules, no longer reset the count:
  • The defense deflects the ball out of bounds.
  • A held ball situation in the offensive backcourt in which the possession arrow favors the offense.
  • A technical foul against the offensive team during possession in its own backcourt.
• Eliminating the five-second "closely-guarded" rule while the ball is being dribbled.
• Allowing for technical fouls to be called on players who are determined to have faked a foul while reviewing for a flagrant foul.
• Allow video replay of shot-clock violations throughout the game. Previously, this type of review was limited to only the final 2:00 of the game and in overtime.
• "Class B" technical fouls, such as hanging on the rim and delay of game, now result in one free throw by the non-violating team instead of the previous two.
• Requiring that a timeout taken 30 seconds or less before a scheduled media timeout break (which are at 16:00, 12:00, 8:00, and 4:00 of each half) become the media timeout. This particular change had been made in NCAA women's basketball effective with the 2013–14 season.
• Stricter enforcement of resumption of play after timeouts, and reducing from 20 seconds to 15 seconds the time allowed to replace a disqualified (fouled out) player. Teams will receive a delay-of-game warning after the first violation, and a Class B technical foul for each subsequent violation.
• Dunking will be allowed during team warmups and halftime.
• An experimental rule allowing players six personal fouls instead of five will be used in all national postseason tournaments except for the NCAA tournament.

• May 27 – The NCAA announced its Academic Progress Rate (APR) sanctions for the 2015–16 school year. A total of 21 programs in 9 sports were declared ineligible for postseason play due to failure to meet the required APR benchmark, including the following four Division I men's basketball teams:^[4]
  • Alcorn State
  • Florida A&M
  • Stetson
  • Central Arkansas
• June 29 – Wisconsin head coach Bo Ryan announced he would retire at the end of the 2015–16 season.^[5]
• August 13 – Ryan backed away from his previously announced retirement plans, saying that he was open to staying on beyond this season and that he would make his decision in the coming months.^[6]
• September 29 – The NCAA announced penalties against SMU following an investigation into a wide array of violations:^[7]
  • The Mustangs were banned from postseason play for 2015–16.
  • Head coach Larry Brown was suspended for nine games.
  • SMU lost nine men's basketball scholarships from 2016–17 through 2018–19. Since the team had only 11 scholarship players for 2015–16, two short of the NCAA limit of 13, the two unused scholarships counted toward the penalty.
  • The men's basketball program was hit with three years' probation.
• October 2 – Yahoo! Sports revealed that the University of Louisville was investigating allegations made in a soon-to-be-published book whose author, a self-described madam, claimed that she had been paid thousands of dollars by former Louisville graduate assistant and director of basketball operations Andre McGee to provide women to dance for and have sex with Cardinals players and recruits.^[8]
• November 10 – The Associated Press preseason All-American team was released. Gonzaga forward Kyle Wiltjer was the leading vote-getter (51 votes). Joining him on the team were Iowa State forward Georges Niang (46 votes), Providence guard Kris Dunn (43), Oklahoma guard Buddy Hield (40) and LSU forward Ben Simmons (28).^[9]
• December 15 – Bo Ryan announced his retirement after a win against Texas A&M–Corpus Christi, effective immediately, with associate head coach Greg Gard assuming the title of interim head coach.^[10]
• December 23 – The NCAA announced penalties against Hawaiʻi for significant violations of NCAA rules:^[11][12]
  • Former head coach Gib Arnold, who had been fired shortly before the 2014–15 season, received a three-year show-cause penalty. An assistant involved in the violations received a two-year show-cause.
  • The Rainbow Warriors were banned from postseason play in 2016–17.
  • The team lost two scholarships in both 2016–17 and 2017–18; it had previously announced a reduction of one scholarship for each of those seasons.
• January 13
  • The NCAA Division I council approved the following changes to its rules regarding declaration for the NBA draft:^[13]
    • Declaration for the draft no longer results in automatic loss of college eligibility. As long as a player does not sign a contract with a professional team outside the NBA, or sign with an agent, he will retain college eligibility as long as he makes a timely withdrawal from the draft.
    • NCAA players now have until 10 days after the end of the NBA Draft Combine to withdraw from the draft. For 2016, the withdrawal date was May 25, about five weeks after the previous mid-April deadline.
    • NCAA players may participate in the draft combine, and are also allowed to attend one tryout per year with each NBA team without losing college eligibility.
    • NCAA players may now enter and withdraw from the draft multiple times without loss of eligibility. Previously, the NCAA treated a second declaration of draft eligibility as a permanent loss of college eligibility.
  • Missouri admitted to major NCAA violations dating to 2011. While the NCAA had yet to announce its findings, Missouri voluntarily imposed the following sanctions:^[14]
    • The Tigers would not participate in any postseason play this season, including the SEC tournament.
    • All 23 of the Tigers' wins in the 2013–14 season were vacated.
    • The Tigers lost one scholarship in each of the next two seasons, and restrict recruiting in 2016–17.
• February 6
  • Louisville self-imposed a 2016 postseason ban.
• March 10
  • The Ivy League announced that it would institute men's and women's conference tournaments effective with the 2016–17 season. The top four teams in the regular-season standings qualify for each tournament. While the tournament winners receive automatic bids to the NCAA men's and women's tournaments, the official conference champions continue to be determined solely by regular-season results. The inaugural editions were held March 11–12, 2017 at the Palestra in Philadelphia.^[15]
• April 8 – The NCAA announced penalties against Southern Miss for a wide array of violations occurring during the tenure of former head coach Donnie Tyndall. The NCAA's findings indicated that mere weeks after Tyndall became head coach, he directed program staffers to complete fraudulent coursework so that several recruits would ostensibly be eligible to play. It was also found that Tyndall had arranged for cash payments to recruits, fabricated documents in an attempt to cover up the payments, and deleted emails relevant to the investigation.^[16]
  • Tyndall received a 10-year show-cause, and even after it expires in 2026, he will be suspended for 50% of his next full season as an NCAA coach. Three of his assistants receive 8-year, 7-year, and 6-year penalties. At the time, Tyndall planned to appeal his penalty.
  • The NCAA accepted the school's self-imposed two-year postseason ban, but placed the Golden Eagles on three years' probation. All wins in which ineligible players participated were vacated, and the Golden Eagles lost four scholarships over the next three seasons.

After a tumultuous four years in which over 80 Division I schools moved to new conferences—some more than once—only two schools joined new conferences as full members for 2015–16:

Another change in membership involved the Western Athletic Conference (WAC). This did not involve a school moving to a new league, but rather a change in identity of a Division I school. During the summer of 2015, the University of Texas–Pan American (UTPA) and the University of Texas at Brownsville (UTB) merged to form the new University of Texas Rio Grande Valley (UTRGV). The UTPA athletic program was inherited by UTRGV, which retained UTPA's WAC membership.

Following UAB's decision to drop football at the end of the 2014 season, its future membership in Conference USA (C-USA) beyond 2014–15 was initially uncertain, as league bylaws require all member schools to either sponsor FBS football or be committed to establishing an FBS program. Due to ongoing efforts by boosters and other supporters to raise funds to bring UAB football back, C-USA indicated that UAB would be allowed to remain in the league for the 2015–16 season, but not beyond that time unless football was reinstated.^[41] On June 1, 2015, UAB initially announced that the football program would be reinstated in 2016,^[42] later pushing back the return of football to 2017; this was sufficient to satisfy C-USA, which announced that it would keep UAB as a member.^[43]

The 2015–16 season was the last for Coastal Carolina in the Big South Conference. On September 1, 2015, the university and the Sun Belt Conference jointly announced that the Chanticleers would join the Sun Belt in July 2016, initially as a non-football member. The football team will join the Sun Belt in 2017, the second year of its transition from FCS to FBS football.^[44]

• The Omaha Mavericks left their home since 2012, the off-campus Ralston Arena, for the new on-campus Baxter Arena. The Mavericks' first game in the new arena was on November 13 against the UC Santa Barbara Gauchos, with the Mavericks losing 60–59.^[45]
• The Ole Miss Rebels also opened a new arena, but unlike Omaha, the move was from one campus venue to another. Tad Smith Coliseum, home to the Rebels since 1966, was replaced by The Pavilion at Ole Miss. The new arena, with a capacity of 9,500, opened on January 7, with the Rebels defeating Alabama 74–66.^[46]