According to the legend, this temple had been built before Ayutthaya became the capital of Thailand, and having been restored all the time by Kings of Ayutthaya Era until the fall of Ayutthaya. Afterwards, the temple was restored in a great restoration project in Rattanakosin Era.

The most important antiquity that is discovered at Thammikarat Temple is the Thammikarat Head which is the head of a big alloy Buddha image, which is artistically and historically significant. The height of the head only is around 2 meters. At present, the head is exhibited at Chao Sam Phraya National Museum. Meanwhile, at Thammikarat Temple, the replica of the head is displayed so that people can worship the head.

There are also ruins of ancient constructions, ancient main hall of the temple and a Sing Lom Chedi (a pagoda that is surrounded with lion statues) which is believed to be the only Sing Lom Chedi that remains in Ayutthaya, as well as the reclining Buddha image in the pantheon and Luang Pho Khao Buddha Image in the main hall of the temple.

Location: On the city island, U-thong Road, Tha Wasukri Sub-district