Su-ngai Kolok (Thai: สุไหงโกลก, Malay: Sungai Golok) is a border town and subdistrict[1] on the Malaysia-Thailand Border in Su-ngai Kolok District, Narathiwat Province, Thailand.

It is also one of the major economic centers in the southern part of Thailand.

Su-ngai Kolok is in the southeastern part of the province.

Adjacent areas are: in the north is Su-ngai Padi and Tak Bai; in the east, Kelantan (Malaysia); in the south, Kelantan (Malaysia) and Wan; in the west Su-ngai Padi.

The township was upgraded to town (thesaban mueang) status on 20 February 2004.