Phnom Bok is a hill in the northeast of the East Baray in Cambodia; with a prasat (temple) of the same name built on it. It is one of a 'trilogy of mountains'; each of which has a temple with similar layout. The creation of the temple is credited to the reign of Yasovarman I (889-910) between the 9th and 10th centuries and was established after he moved his capital to Angkor and named it Yasodharapura. The two other sister temples; named after the contiguous hills; are Phnom Bakheng and Phnom Krom.

The temple is an Angkor monument. It is dedicated to the Trimurti of the Hindu pantheon; Brahma; Vishnu and Shiva. It was built in Bakheng style (893-927) and designed with individual sanctums; which have door openings to the east and west. These are raised on a foundation with a plinth made of laterite stone.