| Mode: | Basketball |
| Year: | 2008–09 |
| Prev Year: | 2007–08 |
| Next Year: | 2009–10 |
| Team: | Oregon State Beavers |
| Conference: | Pacific-10 Conference |
| Short Conf: | Pac-10 |
| Record: | 18–18 |
| Conf Record: | 7–11 |
| Hc Year: | 1st |
| Asst Coach1: | Doug Stewart |
| Ac1 Year: | 1st |
| Asst Coach2: | Nate Pomeday |
| Ac2 Year: | 1st |
| Ac3 Year: | 1st |
| Champion: | CBI Champions |
The 2008–09 Oregon State Beavers men's basketball team represented Oregon State University in National Collegiate Athletic Association (NCAA) Division I men's basketball during the 2008–09 season. Playing in the Pacific-10 Conference (Pac-10) and led by first-year head coach Craig Robinson, the Beavers finished the season with a 18–18 overall record and won the 2009 College Basketball Invitational.[1] [2] It was Oregon State's first-ever postseason tournament championship.[3] Their 12-win improvement over the previous season was the third-highest turnaround in in 2008–09.[4] [5] [6]
In Pac-10 play, the Beavers finished in eighth place with a 7–11 record.[7] They lost in the first round of the 2009 Pac-10 tournament to Stanford, 62–54.
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