The Shah Cheragh (Persian: شاه چراغ, romanized: Shāh-é-Chérāgh, lit. 'King of Light'; Arabic: شاه جراغ, romanized: Šāh-e Čerāḡ) is a Twelver Shi'ite funerary monument and religious complex located in Shiraz, in the province of Fars, Iran. The 12th-century complex is centred around the mausoleum of Sayyid Ahmad, the son of Musa al-Kazim, who is known as Shah Cheragh (King of Light) in local traditions, and hence the building's name.

The complex was added to the Iran National Heritage List on 10 June 1942, administered by the Cultural Heritage, Handicrafts and Tourism Organization of Iran. The complex is one of the holiest sites in Twelver Shia Islam.

Archaeological excavation indicates that there was a settlement on the site of Shiraz in the prehistoric period and cuneiform records from Persepolis, 57 kilometres (35 mi) to the north, show that Shiraz was a significant town in Achaemenian times. As a city however, it was founded in 684 CE, after the Arab armies conquered the Sassanians. The Buyids (945-1055 CE) made Shiraz their capital, building mosques, palaces and a great city wall. The 13th and 14th centuries saw Shiraz as a literary center, especially famous for poets Sa'adi and Hafez, both of whom are buried in the city. There are many splendid Islamic monuments in Shiraz, especially its enormous Jameh Mosque of Atigh.

Following the Abbasid persecution of the Shi'ite sect, Sayyid Ahmad ibn Musa (also known as Syed Amir Ahmad) and his brother, Muhammad ibn Musa al-Kazim, both of whom were brothers of Ali al-Rida, took refuge in Shiraz. Amir Ahmad died or was murdered in 835 AH (1431/1432CE). The first structure over his grave, a simple domed mausoleum, was built in the 13th century during the rule of the Salghurids, by the minister, a former Buyid prince, attributed to Atabak Sa'ad Ebn-e-Zangi.

Local folklore tells that the grave was found when a light appeared over it, which caught the attention of the people, who told the minister about what they had seen. The tombs of both brothers became celebrated pilgrimage destinations in the 14th century, during the rule of the Injuids, when Queen Tashi Khatun, the mother of Ishaq Injoo, further expanded the structure, and erected a mosque and madrasa over the tomb.

During the Safavid era in the 16th century, the building was extensively renovated. Then in the 18th century, Nader Shah donated a golden chandelier, which was hung under the dome. But a few years later, an earthquake struck Shiraz, and the complex of Shah Cheragh was heavily damaged by the tremors. The golden chandelier was lost during this time. A year after the earthquake, a man named Qandeel found some remains of the donated gold, which he used to fund the reconstruction of the Shah Cheragh funerary monument.

In 1243 AH (1827/1828 CE), during the reign of Fath-Ali Shah Qajar, the second ruler of the Qajar dynasty, several repairs were made to the building; including a silver zarih installed around the grave. In 1958 CE, the dome was reconstructed.

The complex consists of a mosque, the mausoleum of Sayyid Ahmad ibn Musa, and, in more recent times, a history museum.