The Cohansey River, also called Cohansey Creek, is a 30.6-mile-long (49.2 km) river in southern New Jersey of the United States. It drains approximately 108 square miles (280 km) of rural agricultural and forested lowlands on the north shore of Delaware Bay.
It rises in central Salem County approximately 5 miles (8 km) southeast of Woodstown, and flows south through rural Cumberland County. It flows through Sunset Lake, which is also fed from Mary Elmer Lake, both of which are located in the park system of the city of Bridgeton.