Rasau, formerly known as Kampong Rasau, is an area located in Brunei within the Belait District. It is situated on the west bank of the Belait River, positioned just south of Kampong Sungai Teraban and in close proximity to the administrative center of Kuala Belait.
The area serves a dual purpose as both a village and one of Brunei's oil fields. Historically, Rasau was classified as one of the villages within Mukim Kuala Belait.