Koca Mustafa Pasha Mosque (Turkish: Koca Mustafa Paşa Camii; also named Sünbül Efendi Camii) is a former Eastern Orthodox church converted into a mosque by the Ottomans, located in Istanbul, Turkey. The church, as the adjoining monastery, was dedicated to Saint Andrew of Crete, and was named Saint Andrew in Krisei or by-the-Judgment (Greek: Μονὴ τοῦ Ἁγίου Ἀνδρέου ἐν τῇ Κρίσει, Monē tοu Hagiοu Andreοu en tē Krisei). Although heavily transformed during both the Byzantine and the Ottoman eras, it is one among the few churches in Istanbul still extant, whose foundation goes back to the sixth century.