Chalong Mayor Thanaporn Ongsantiphap reported that firefighters were called to the temple, on Chao Fa East Rd, at about 12:40pm.
The fire teams soon had the blaze extinguished, but by then the damage had been done.
No estimate of the damage done by the fire has been reported yet, but photos of the scene show extensive damage to the inside of the building.
The building is owned and maintained by the Phuket Cultural Office.
No injuries were reported as a result of the fire.
Investigators have yet to confirm what started the blaze.