Goharshad Mosque (Persian: مسجد گوهرشاد) is a former free standing mosque in Mashhad of the Razavi Khorasan Province, Iran, which now serves as one of the prayer halls within the Imam Reza shrine complex.
It was built by the order of Queen Goharshad, the wife of Shah Rukh of the Timurid Dynasty in 1418 CE. The architect of the edifice was Ghavameddin Shirazi, who is responsible for so many of Shah Rukh's great buildings, with the architectural and decorative manpower supplied from Shiraz and Isfahan.
The mosque underwent some renovations during the Safavid and Qajar eras. It has four iwans and a courtyard measuring 50 m × 55 m (160 ft × 180 ft), as well as several shabestans.
The double layered dome of the mosque was severely damaged in 1911 in bombings by troops of the Russian Empire.