The Jōganji River (Jōganji-gawa) is a river in Toyama Prefecture, Japan, that flows through the city of Toyama and the town of Tateyama. The river had previously been called the Nii River (Nii-kawa).
The river originates in the Tateyama Mountains in the southeastern portion of the city of Toyama. From there, it flows northwest, forming the border between Toyama and Tateyama. From there, it cuts through Toyama before emptying into Toyama Bay.