Kazan Cathedral or Kazanskiy Kafedralniy Sobor ( Каза́нский кафедра́льный собо́р), also known as the Cathedral of Our Lady of Kazan, is a cathedral of the Russian Orthodox Church on the Nevsky Prospekt in Saint Petersburg. It is dedicated to Our Lady of Kazan, probably the most venerated icon in Russia.

The construction was started in 1801 and continued for ten years while being supervised by Alexander Sergeyevich Stroganov. Upon its completion in 1811, the new temple replaced the Church of Nativity of the Theotokos, which was disassembled when the Kazan Cathedral was consecrated.

It was modelled by Andrey Voronikhin after the St. Peter's Basilica in Rome. Some art historians assert that Emperor Paul intended to build a similar church on the other side of Nevsky Prospect that would mirror the Kazan Cathedral but his plans failed to materialize. Although the Russian Orthodox Church strongly disapproved of the plans to create a replica of a Catholic basilica in Russia's then capital, several courtiers supported Voronikhin's Empire Style design.

The cathedral's interior, with its numerous columns, echoes the exterior colonnade and is reminiscent of a palatial hall, being 69 metres in length and 62 metres in height. The interior features numerous sculptures and icons created by the best Russian artists of the day. A wrought iron grille separating the cathedral from a small square behind it is sometimes cited as one of the finest ever created.