| Birth Date: | 4 July 1975 |
| Birth Place: | South Korea |
| Weight: | 96kg (212lb) |
| Ru Position: | Flanker |
| Clubs1: | Korea Electric Power |
| Repcaps1: | 26 |
| Hangul: | 백광수 |
| Hanja: | ! |
| Mr: | Paek Kwangsu |
| Rr: | Baek Gwangsu |
Back Kwang-soo (born 4 July 1975) is a South Korean rugby union footballer. He plays at the flanker position.
He played for Korea Electric Power, in South Korea. He is one of the best players for the Korea national rugby union team and he's currently the most capped for his country with 26 matches.