Le Mans Cathedral (Cathédrale St-Julien du Mans) is a Catholic cathedral situated in Le Mans, France. It is dedicated to Saint Julian of Le Mans, the city's first bishop, who established Christianity in the area around the beginning of the 4th century.

The cathedral, which combines a Romanesque nave and a High Gothic choir, is notable for its rich collection of stained glass and the spectacular bifurcating flying buttresses at its eastern end.