| Karl Markt | |
| Birth Date: | 8 March 1980 |
| Birth Place: | Zams, Austria |
| Discipline: | Mountain |
| Role: | Rider |
| Ridertype: | Cross-country |
Karl Markt (born 8 March 1980) is an Austrian cross-country mountain biker. At the 2012 Summer Olympics, he competed in the Men's cross-country at Hadleigh Farm, finishing in 20th place.