This temple is called by general people as "WAT YAI" or "WAT LUANG POR PHRA BUDDHA CHINNARAJ" Phrabat Somdej Phra Mongkutklao ( King Rama VI ) classified as "Vora Maha Viharn" or the first grade of Royal Temple in the year of 1915 (B.E.2458). At the present , Wat Yai is named " Wat Phra Sri Rattana Mahathat"
Wat Phra Sri or Wat Yai situates on the east bank of Nan River opposite the Phitsanulok City Hall. Prince Damrong Rajanupab said about Wat Phra Sri Rattana Mahathat.
"The temple is a big and more important than other temples in Phitsanulok and is believed that was built in the Sukhothai period being renovated form time to time".
The temple was built in the time of Phra Maha Dhamma Raja (King Li Thai) alias Phra Chao Sri Dhamma Tri Pidok when the town of Songkwai(Phitsanulok) was built in 1357 (B.E.1900). The Northern history stated that.
In the year of 1357 Phra Chao Sri Dhamma Tri Pidok (Phra Maha Dhamma Raja ,King Li Thai) was a pious king, a true believer in the Buddhism. He studied the Tri-Pidok and teachings of other religions fluently. He built up Wat Phra Sri Mahathat on the east side with a Pagoda in the middle compounds, 4 Viharns in the 4 corners with 2 terraces and casted 3 Buddha images as Main Buddha in the temple.