Wat Phra Si Sanphet was built in 1448 A.D. on the site which had served for the royal palace from 1350 to 1448 spanning the reigns of King Ramathibodi I to King Sam Phraya. King Borommatrailokanat ordered the wat built to be utilized as a monastic area.
Wat Phra Si Sanphet was used as the royal chapel and, therefore, did not have a Sangavasa (a dwelling for monks). The wat was used for various royal ceremonies and rituals. When the Burmese sacked Ayutthaya in 1767. the gold that covered the Buddha image and other decorations was stripped away and taken by the invaders. King Rama I (1782-1809) transferred the core of Phra Buddha Chao Si Sanphet to Wat Phra Cetuphon in Bangkok.