| Riaan Viljoen | |
| Birth Date: | 1 April 1983 |
| Birth Place: | Carletonville, South Africa |
| Height: | 1.79m (05.87feet) |
| Weight: | 900NaN0 |
| School: | Klerksdorp High School, South Africa |
| Position: | Fullback / Flyhalf / Wing |
| Currentclub: | / NTT DoCoMo Red Hurricanes |
| Youthyears1: | 2002–2003 |
| Years1: | 2005–2007 |
| Apps1: | 57 |
| Points1: | 218 |
| Years2: | 2008–2011 |
| Apps2: | 74 |
| Points2: | 308 |
| Years3: | 2009–2011 |
| Apps3: | 26 |
| Points3: | 45 |
| Years4: | 2010 |
| Clubs4: | → |
| Apps4: | 1 |
| Points4: | 0 |
| Years5: | 2012–2013 |
| Apps5: | 23 |
| Points5: | 40 |
| Years6: | 2012–2013 |
| Apps6: | 11 |
| Points6: | 24 |
| Years7: | 2013–2015 |
| Clubs7: | NTT DoCoMo Red Hurricanes |
| Apps7: | 28 |
| Points7: | 97 |
| Years8: | 2015 |
| Apps8: | 14 |
| Points8: | 25 |
| Years9: | 2015–present |
| Apps9: | 15 |
| Points9: | 16 |
| Years10: | 2016–present |
| Clubs10: | NTT DoCoMo Red Hurricanes |
| Apps10: | 0 |
| Points10: | 0 |
| Repyears1: | 2009 |
| Repcaps1: | 2 |
| Reppoints1: | 0 |
| Clubupdate: | 22 July 2016 |
| Repupdate: | 12 October 2015 |
Riaan Viljoen (born 1 April 1983) is a professional South African rugby union rugby player, currently playing with Japanese Super Rugby side the and Top League West side NTT DoCoMo Red Hurricanes. He was born in Carletonville, South Africa and his first tour with the Springboks was to France, Italy, Ireland and England in late 2009 where he played in two touring matches. He signed with the Sharks for the 2012 and the 2013 Super Rugby tournaments.
In 2013, he signed a deal to play in the Top League in Japan for NTT DoCoMo Red Hurricanes.[1] For 2016 he joined the new Japanese Super Rugby team Sunwolves.