| Birth Place: | Tampere, Finland |
| Height: | 171 cm |
| Weight: | 75-92 kg |
| Sport: | Weightlifting |
| Show-Medals: | yes |
Jaakko Rafael Kailajärvi (born 1 July 1941) is a retired Finnish weightlifter who set two light-heavyweight world records in the snatch in 1962. He placed second-third in this event at the 1972 and 1974 world championships. Kailajärvi competed in light-heavyweight and middle-heavyweight divisions at the 1964, 1968, 1972 and 1976 Olympics with the best result of fifth place in 1968. His elder brother Jouni was also an Olympic weightlifter.