Bart Lemmen (born 14 October 1995) is a Dutch racing cyclist, who currently rides for UCI WorldTeam Visma–Lease a Bike.

Lemmen started his cycling career relatively late, after graduating Dutch Royal Military Academy and working as an officer in the Royal Netherlands Air Force as a platoon commander in airfield protection, rising to the rank of captain.

In June 2024 he was a late addition to the Visma–Lease a Bike team for the 2024 Tour de France when Sepp Kuss did not recover sufficiently from COVID-19.