The Church of the Virgin of the Pharos (Greek: Θεοτόκος τοῦ Φάρου, Theotokos tou Pharou) was a Byzantine chapel built in the southern part of the Great Palace of Constantinople, and named after the tower of the lighthouse (pharos) that stood next to it. It housed one of the most important collections of Christian relics in the city, and functioned as the chief palatine chapel of the Byzantine emperors.

History
The church was probably built sometime in the 8th century, as it is first attested in the chronicle of Theophanes the Confessor for 769: it was there that the future emperor Leo IV (r. 775–780) married Irene of Athens.The church was located close to the ceremonial heart of the palace, the throne room of the Chrysotriklinos and the adjoining imperial apartments.Following the end of iconoclasm, it was extensively rebuilt and redecorated by Emperor Michael III (r. 842–867).As restored, it was a relatively small building with a ribbed dome, three apses, a narthex and a "splendidly fashioned" atrium.On the occasion of its rededication, probably in 864, the Patriarch Photios held one of his most famous homilies lauding the church's spectacular decoration. Indeed, Photios takes the unusual step of criticizing the church, albeit subtly, for being too sumptuous, especially given its small size.

Together with the churches of St Stephen in the Daphne Palace and the Nea Ekklesia, the Virgin of the Pharos came to hold one of the major collections of Christian holy relics. Consequently, and because of its proximity to the imperial quarters, it became one of the major ceremonial locations of the imperial palace,eventually rising to be, in the words of Cyril Mango, the "palatine chapel par excellence".