[1] Top-seeded host Montana defeated two-time defending champion Idaho in the championship game, 76–68, to win their first Big Sky tournament title.
[2] No new teams were added to the Big Sky prior to the 1990–91 season, leaving total membership at nine.
No changes were made to the tournament format, except that host site was not predetermined and went to the regular season champion.
Source:[4][5] The Grizzlies gained the automatic bid to the NCAA tournament, and no other Big Sky members were invited.
Boise State hosted a first-round game in the NIT, but lost by a point to Southern Illinois.