Sai Yok Noi is a waterfall, also known as Khao Phang Waterfall, in the Tenasserim Hills, Sai Yok District of Kanchanaburi Province, Thailand, near the town Nam Tok Sai Yok Noi. It is the most popular attraction of the Sai Yok National Park. The waterfall consists of the limestone cliffs collapsing and that became the origin of the name "Khao Phang Waterfall”. The upstream falls from the mountain and flows along the limestone cliffs about 15-meter high. It is popular among domestic and foreign tourists alike, in part because it lies next to the province's trunk road alongside which there is ample parking space.