1985–86 Idaho Vandals men's basketball team

The 1985–86 Idaho Vandals men's basketball team represented the University of Idaho during the 1985–86 NCAA Division I men's basketball season. Members of the Big Sky Conference, the Vandals were led by third-year head coach Bill Trumbo, and played their home games on campus at the Kibbie Dome in Moscow, Idaho.

Prior to the season, the coaches picked Idaho to finish fifth in the conference, and the media had them at sixth. The Vandals returned all but one starter from the previous year, but were 11–17 overall in the regular season and 4–10 in conference play, last in the standings for a third consecutive year. At the conference tournament in Reno, they met second-seed Montana in the quarterfinals and lost by eight points, their  third consecutive loss in the Big Sky quarterfinals.

In three seasons, Trumbo's teams were .310 overall (.210 in conference) and he was relieved of his duties in March, succeeded by Tim Floyd, an assistant under hall of fame head coach Don Haskins at Texas-El Paso.

Postseason result
!colspan=6 style=| Big Sky tournament