The Amir Jamal al-Din al-Ustadar Mosque (), also known as the Gamal al-Din Mosque, is a mosque-madrasa located on Al-Tambakshiya Street, in Islamic Cairo, Egypt. To the southeast of the mosque is Habas al-Rahb Street.
The mosque was built in 1407 CE by and dedicated to Emir Jamal al-Din al-Ustadar, who served under the Burji Mamluk Sultan An-Nasir Faraj. The building served as a madrasa which taught all four Islamic schools of jurisprudence. Renovation of the building was completed in 2001.
The architectural style of the mosque is greatly influenced by the Mosque-Madrassa of Sultan Barquq. Although Jamal al-Din was an influential patron of many of the architectures during his era, his career was tumultuous and he was not mourned after his execution by Sultan An-Nasir. At the same time, the Sultan had attempted to tear down this mosque, but it was prevented by the qadi by erasing the name of Jamal al-Din from the mosque.
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