The Théâtre de la Porte Saint-Martin (French pronunciation: [teɑtʁ də la pɔʁt sɛ̃ maʁtɛ̃]) is a venerable theatre and opera house at 18, Boulevard Saint-Martin in the 10th arrondissement of Paris.

It was first built very rapidly in 1781 under the direction of Nicolas Lenoir [fr] (1726–1810) to house the Paris Opéra, whose previous home, the second Salle du Palais-Royal, had burned down on 8 June 1781.

The new theatre had a capacity of about 2,000 spectators and included a parterre with the lowest-priced tickets sold only to males who stood throughout the performances, an amphitheatre, and four rows of boxes.

[1][2] The theatre was destroyed by fire during the Paris Commune of 1871 and replaced in 1873 with a building designed by the architect Oscar de la Chardonnière (d. 1881), who enlisted the aid of the sculptor Jacques-Hyacinthe Chevalier (1825–1895) in the design of the new facade.

Three of the above were the basis of opera libretti: The theatre's other productions have included the ballet Leda, the Swiss Milkmaid (1823) and works by Dany Boon, Charles-Gaspard Delestre-Poirson and Gaston Arman de Caillavet.