Lavaur Cathedral (Cathédrale Saint-Alain de Lavaur) is a former Roman Catholic cathedral, and national monument of France, located in the town of Lavaur, Tarn.

Until the French Revolution this was the seat of the diocese of Lavaur now held by the Archbishop of Albi.

The cathedral is dedicated to Saint Alan of Lavaur. The present structure dates from the 13th, 14th and 15th centuries, and has an octagonal bell-tower. A second, smaller square tower contains a 16th century jaquemart (a statue which strikes the hours with a hammer). In the bishop's garden is the statue of Emmanuel, comte de Las Cases, one of the companions of Napoleon on Saint Helena.