The Naf River (Bengali: নাফ নদী Naf Nodi IPA: [naf nod̪i]; Burmese: နတ်မြစ် [naʔ mjɪʔ]; Rakhine: နတ်မြစ် [nɛ́ mràɪʔ]) is an international river marking part of the border of southeastern Bangladesh and northwestern Myanmar.

It flows into the Bay of Bengal in the Indian Ocean, between the Bangladeshi Cox's Bazar District of the Chittagong Division, and the Burmese Rakhine State.

Historically, Shapuree Island, located at the mouth of the river, has played an important role territorially.

St. Martin's Island is also at the river's mouth.

Regular incidents in which fishermen and Burmese refugees are shot at by the Tatmadaw (Myanmar Armed Forces), and/or refugees fleeing Myanmar are escorted back to Myanmar by Bangladeshi troops have occurred on the Naf River.