Kai Shan () is a hill in Wang Chau, in the New Territories of Hong Kong, separating the new towns of Yuen Long and Tin Shui Wai. It has a height of .
Kai Shan is a private property and is owned by the Tang clan. According to reports, the hill is burned regularly to keep the vegetation low.
It has a popular neighborhood trail where locals have planted flowers and created art, the top of which has exceptional views of both Yuen Long and Shenzhen.