The Zengwun River (Chinese: 曾文溪; Pe̍h-ōe-jī: Chan-bûn-khoe; Tsengwen River)is a river in Taiwan. It flows through Tainan City and Chiayi County for 130km.
Located upstream of Zengwun River is the largest reservoir in Taiwan, Zengwun Reservoir, formed by Zengwun Dam. The endangered black-faced spoonbills come every winter as migrants and inhabit downstream near the estuary, where many other waterfowls are also found. A conservation area has been set up to protect the spoonbills.