| Year: | 1938 |
| Team: | Hawaii Rainbows |
| Sport: | football |
| Conference: | Independent |
| Record: | 4–4 |
| Head Coach: | Otto Klum |
| Hc Year: | 18th |
| Stadium: | Honolulu Stadium |
| Bowl: | Poi Bowl |
| Bowl Result: | L 7–32 vs. UCLA |
The 1938 Hawaii Rainbows football team represented the University of Hawaiʻi (now known as the University of Hawaiʻi at Mānoa) as an independent during the 1938 college football season. Led by 18th-year head coach Otto Klum, the Rainbows compiled an overall record of 4–4.