| Birth Date: | 23 March 1927 |
| Birth Place: | Tjörnarp, Sweden |
| Death Date: | 15 March 2009 (aged 81) |
| Death Place: | Helsingborg, Sweden |
| Height: | 1.76m (05.77feet) |
| Weight: | 68kg (150lb) |
| Sport: | Athletics |
| Event: | 3000 metres steeplechase |
| Club: | IFK Växjö, IFK Helsingborg |
| Pb: | 3000 mS – 8:41.2 (1961) |
| Show-Medals: | yes |
Karl Gunnar Alfred Karlsson-Tjörnebo (23 March 1927 – 15 March 2009) was a Swedish long-distance runner who specialized in the 3000 metres steeplechase. He competed at the Olympic Games three times, with a twelfth place in 1952, a fifth place in 1960 and failed to reach the final in 1956. At home, he won six national championships between 1951 and 1961, and set four Swedish records in his main event.