| Year: | 2009 |
| Team: | Cal Poly Mustangs |
| Sport: | football |
| Conference: | Great West Conference |
| Short Conf: | GWC |
| Record: | 4–7 |
| Conf Record: | 1–3 |
| Head Coach: | Tim Walsh |
| Hc Year: | 1st |
| Cooff Coach1: | Brian Cook |
| Cooc1 Year: | 1st |
| Cooff Coach2: | Saga Tuitele |
| Cooc2 Year: | 1st |
| Def Coach: | Greg Lupfer |
| Dc Year: | 1st |
| Stadium: | Alex G. Spanos Stadium |
The 2009 Cal Poly Mustangs football team represented California Polytechnic State University, San Luis Obispo as member of the Great West Conference (GWC) during the 2009 NCAA Division I FCS football season. Led by first-year head coach Tim Walsh, Cal Poly compiled an overall record of 4–7 with a mark of 1–3 in conference play, placing last out of five teams in the GWC. The Mustangs played home games at Alex G. Spanos Stadium in San Luis Obispo, California.