Wat Phra Si Sanphet (Thai: วัดพระศรีสรรเพชญ์; "Temple of the Holy, Splendid Omniscient") was the holiest temple on the site of the old Royal Palace in Thailand's ancient capital of Ayutthaya until the city was completely destroyed by the Burmese in 1767, during the Burmese–Siamese War.

[1] It was the grandest[2] and most beautiful temple in the capital and it served as a model for Wat Phra Kaew in Bangkok.In 1350 U-thong, also known as King Ramathibodi I, ordered the construction of a royal palace in the same area that Wat Pra Si Sanphet stands today.

[3] In 1499 a viharn, or hall of worship, called “Vihara Luang” (Royal Chapel) was built on the palace grounds.

[1] King Ramathibodi II gave orders for a gigantic image of Buddha to be cast, and installed in Wat Si Sanphet.

[4] This statue, called “Phra Si Sanphetdayan”, was the main object of veneration within the royal chapel.

Unfortunately, the city of Ayutthaya, including the temple compounds, were completely destroyed in the Burmese invasion in 1767, with the exception of the three Chedis that can be seen today.

In 1767, the Burmese conquered the capital of Ayutthaya and began the extensive destruction and looting of numerous temples and other buildings, including the Wat Phra Si Sanphet.

The terrace of the Chedi with Mondop was surrounded by a cloister (Phra Rabieng), in each case a hall was built in the west and in the east, an arrangement as can be seen in many temples in the country today.

Around the entire complex there drew a high perimeter wall, four gates passages in the four directions offered access to the temple.