The Golden Buddha is believed to be 700 to 800 years old as it is in the Mara attitude, typical of the Sukhothai era. It was installed at Wat Phrayakrai in the Yannawa area of Bangkok during the reign of King Rama III where it stayed until 1931.

The temple had fallen out of use and was abandoned so the Ecclesiastical Commission had it relocated at Wat Trai Mit. At this time, no one seemed to know that it was made of pure gold.

Then in 1955, Reverend Phra Visutha-thibordee, the presiding abbot at the temple had supervised the construction of the temple building to house the Buddha. When it was being moved into its new position, the covering plaster was damaged revealing what was inside -  Buddha image cast in 18 carat gold.

It is believed that the original Golden Buddha was disguised under the plaster covering to hide it from enemies during the Ayutthaya period. Photographs of different stages of the plaster removal are displayed in the Wihan.