| Birth Date: | 25 April 1970 |
| Birth Place: | Siegen, West Germany |
| Height: | 1.75m (05.74feet) |
| Weight: | 65kg (143lb) |
| Sport: | Swimming |
| Club: | Schwimm Gemeinschaft DAB Hansa Dortmund |
Katja Ziliox (also Zillox; born 25 April 1970) is a retired German swimmer who won a bronze medal at the 1989 European Aquatics Championships. She also competed at the 1988 Summer Olympics in the 200 m backstroke, and 100 m and 4 × 100 m freestyle events and finished seventh in the relay.