The Imo River (Igbo:Imo) is located in southeastern Nigeria and flows 240 kilometres (150 mi) into the Atlantic Ocean. In Akwa Ibom State, the river is known as Imoh River, that is, Inyang Imoh, which translates to River of Wealth. Its estuary is around 40 kilometres (25 mi) wide, and the river has an annual discharge of 4 cubic kilometres (1.0 cu mi) with 26,000 hectares of wetland. The Imo's tributary rivers are the Otamiri and Oramirukwa. The Imo was cleared under the British colonial administration of Nigeria in 1907–1908 and 1911; first to Aba and then to Udo near Umuahia.

Imo State is a state in the South-East geopolitical zone of Nigeria, bordered to the north by Anambra State, Rivers State to the west and south, and Abia State to the east. It takes its name from the Imo River which flows along the state's eastern border. The state capital is Owerri and the State's slogan is the "Eastern Heartland."