The Boulevard du Montparnasse () is a two-way boulevard in Montparnasse, in the 6th, 14th and 15th arrondissements of Paris.
The boulevard runs south-eastward from the to the Port-Royal () and is 1.7km in length. The Tour Montparnasse and place du 18 juin 1940 are located along it.
During the 1930s, when American writer Henry Miller was penniless in Paris, he would often sleep on a bench outside the Closerie des Lilas, a brasserie located at 171 Boulevard du Montparnasse.