| Full name | Christian "Tian" Viljoen |
|---|---|
| Country (sports) |  South Africa |
| Born | 10 April 1961 Pretoria, South Africa |
| Height | 1.93 m (6 ft 4 in) |
| Plays | Right-handed |
| Singles | |
| Career record | 5–7 |
| Career titles | 0 |
| Highest ranking | No. 282 (4 January 1982) |
| Grand Slam singles results | |
| Wimbledon | 2R (1983) |
| Doubles | |
| Career record | 35–33 |
| Career titles | 0 |
| Highest ranking | No. 49 (3 January 1983) |
| Grand Slam doubles results | |
| French Open | 3R (1983) |
| Wimbledon | 3R (1983) |
| US Open | 3R (1983) |
Christian "Tian" Viljoen (born 10 April 1961) is a former professional tennis player from South Africa. He enjoyed most of his tennis success while playing doubles. During his career, he finished runner-up in doubles at three events. He achieved a career-high doubles ranking of world No. 49 in January 1983.