Wat Sai (Thai: วัดไทร, formerly spelled วัดไซ, pronounced [wát sāj]) is an old Buddhist temple in Bangkok.

[1] In 1708, the temple received the Wisungkhamsima and was officially promoted as a community place of worship.

[1] Another interesting attraction is Tamnak Thong (ตำหนักทอง, "gold painted mansion"), kindly dedicated by King Sanphet VIII.

[2] Beside the temple next to the canal Khlong Dan, is the location of Wat Sai floating market.

It was once a busy and lively floating market where farmers came and sold products on boat.