The temple was restored again during the reign of Kin Borommakot (1732-1758) and four porticos were added to the main prang. The temple was burned during the sacking of Ayutthaya in 1767.
Wat Mahathat, a royal monastery, served as the seat of the Sangaraja, the head of the Buddhist monks of the Kamavasi Sect, since the time of the Mahathera Thammakanlayan who built the Wat. This Wat at one time housed an unusual Buddha image made of green stone and seated on a throne. The image was moved to Wat Na Phra Meru in the Rattanakosin Period by King Rama III.