The Cathedral of Intercession of Theotokos on the Moat  is a Russian Orthodox cathedral erected on the Red Square in Moscow in 1555–1561. Built on the order of Ivan IV of Russia to commemorate the capture of Kazan and Astrakhan, it marks the geometric center of the city and the hub of its growth since the 14th century. It was the tallest building of Moscow until the completion of the Ivan the Great Bell Tower in 1600.

The cathedral foreshadowed the climax of Russian national architecture in the 17th century but has never been reproduced directly.

The cathedral has operated as a division of the State Historical Museum since 1928. It was completely secularized in 1929[9] and, as of 2009, remains a federal property of the Russian Federation. The cathedral has been part of the Moscow Kremlin and Red Square UNESCO World Heritage Site since 1990.