Pattani River (Thai: แม่น้ำปัตตานี, RTGS: Maenam Pattani, Thai pronunciation: [mɛ̂ːnáːm pàt.taː.niː]) is a river in Southern Thailand, Thailand. It originates in Betong district, Yala Province and mouths into the Gulf of Thailand at the town Pattani. Within Yala province the river forms the Bang Lang Reservoir. The river has a length of 214 km.
The Bang Lang dam is built on the river.