Monastery of Stoudios is a ruined Byzantine monastery located in Istanbul, Turkey. It was founded in 462 AD by the consul Flavius Studius, a Roman patrician who had settled in Constantinople, and was consecrated to Saint John the Baptist. The monastery was later converted by Ottoman Sultan Bayezid II into a mosque named İmrahor Mosque. The monastery was inscribed as a UNESCO World Heritage Site in 1985 as part of Historic Areas of Istanbul.