Duplin River, Tidal creek in McIntosh County, United States.

Duplin River is a tidal creek in McIntosh County that runs along the western edge of Sapelo Island before flowing south into Doboy Sound and the Atlantic Ocean. The waterway connects salt marshes and maritime environments through its winding path along the coastal landscape.

The Duplin River is an 8.1-mile tidal channel in McIntosh County, Georgia, running north to south along the western edge of Sapelo Island into Doboy Sound. Its name and course appear on coastal charts of the Sapelo Island area, where the river separates the island from the mainland marshes. The channel carries tidal water between the salt marshes and the Atlantic throughout each day.

The Duplin River forms the western boundary of Sapelo Island, a barrier island long associated with Gullah-Geechee communities, and the tidal creek and its salt marshes are worked today by shrimp boats and crab traps set along the McIntosh County shore. The river's name is shared with Duplin County in North Carolina, though the two are unrelated in origin.

The Duplin River has no road access and no boat ramp; it is reached only by boat from Doboy Sound or from the Sapelo Island ferry landing area. Its 8.1-mile channel runs north to south along the island's western edge, so plan the return leg against a flooding tide. Mudflats and marsh grass line both banks, and the water is shallow outside the main channel.

The Duplin River is a tidal river, not a freshwater stream: its 8.1-mile (13.0 km) course runs north to south along the western edge of Sapelo Island into Doboy Sound, so its flow reverses with the tide rather than running one way.