德默拉拉河是圭亚那的河流，位于该国东部，河道全长345公里，发源自该国中部雨林，最终注入大西洋，河口处距离林登105公里，河畔城镇有乔治敦。

The Demerara River is a river in eastern Guyana that rises in the central rainforests of the country and flows to the north for 346 kilometres until it reaches the Atlantic Ocean. Georgetown, Guyana's largest seaport and capital, is situated on the east bank of the river's mouth. The Demerara's estuary is narrow and the flowrate is rapid. This scouring action maintains a 5-to-6-metre-deep direct channel to the ocean. The river's deep brown color is primarily the result of the massive quantities of silt carried from upriver by the powerful currents. So powerful are these currents, that the ocean retains the Demerara's brown color for a considerable distance out to sea.