Karel Nesl was a cyclist from Czechoslovakia who was active during the 1950s. After winning a stage of the Tour of East Germany in 1951, Nesl then won the gruelling Praha–Karlovy Vary–Praha one-day race in 1952. These performances earned him a place on the Olympic team for the Helsinki Games where he competed in the individual road race, but did not finish the course. Arguably his best result came in 1954 when he became the inaugural winner of the Tour of Slovakia, winning three stages of the race along the way. Nesl also rode in several editions of the Peace Race, finishing 17th in 1953.