The Great Mosque of Herat (Persian: مسجد جامع هرات‎, Masjid-i Jāmi‘-i Herāt) or "Jami Masjid of Herat", is a mosque in the city of Herat, in the Herat Province of north-western Afghanistan. It was built by the Ghurids, under the rule of the Sultan Ghiyath al-Din Muhammad Ghori, who laid its foundation in 1200 CE, and later extended by several rulers as Herat changed rulers down the centuries from the Timurids to the Safavids, Mughals and then the Uzbeks, all of whom supported the mosque. Though many of the glazed tiles have been replaced during subsequent periods, the Friday Mosque in Herat was given its present form during the closing years of the fifteenth century.

Apart from numerous small neighborhood mosques for daily prayer, most communities in the Islamic world have a larger mosque, a congregational mosque for Friday services with a sermon. The Jama Masjid was not always the largest mosque in Herat; a much larger complex the Mosque and Madressa of Gawhar Shad, also built by the Timurids, was located in the northern part of the city. However, those architectural monuments were dynamited by officers of the British Indian Army in 1885, to prevent its use as a fortress if a Russian army tried to invade India.