The Pandaruan River (Malay: Sungai Pandaruan) is an international river on the island of Borneo. The river mouth is on Brunei Bay.
There is a ferry service across the river.
The river forms part of the international border between Brunei and Malaysia. The river separates Limbang District, Sarawak, Malaysia and the Temburong District, an isolated exclave of Brunei.
- Renate Haller-Trost (1994). The Brunei–Malaysia Dispute over Territorial and Maritime Claims in International Law, (Maritime Briefing: Durham, UK)
Coordinates: Earth 4°47′42″N 115°02′25″E / 4.79500°N 115.04028°E