| Rhys Williams | |
| Birth Name: | Gethin Rhys Williams |
| Birth Date: | 23 February 1980 |
| Birth Place: | Cardiff, South Glamorgan, Wales |
| Weight: | 13 st 7 lb (86 kg) |
| School: | Ysgol Iolo Morganwg Cowbridge Comprehensive School |
| Ru Position: | Full Back, Wing, Centre |
| Youthyears1: | |
| Years1: | 1998-2008 |
| Clubs1: | Cardiff Blues |
| Apps1: | 181 |
| Points1: | 265 |
| Superyears1: | |
| Repyears1: | 2000-2005 |
| Repteam1: | Wales |
| Repcaps1: | 44 |
| Reppoints1: | 80 |
| Ru Sevensnationalyears1: | |
Gethin Rhys Williams (born 23 February 1980 in Cardiff) is a Welsh rugby union player who played for Cardiff Blues and won 44 caps for the Wales national rugby union team as a full-back and winger. During the 2005-2006 season Williams was the captain of the Cardiff Blues.