Kushiro River (釧路川, Kushiro-gawa) is a river in Hokkaidō, Japan. It is 154 kilometers (96 mi) in length and has a drainage area of 2,510 square kilometers (970 sq mi). The Kushiro originates from Lake Kussharo and flows south across the . The river is joined by two tributaries, the (60.2 kilometres (37.4 mi)) and the Setsuri River (59.8 kilometres (37.2 mi)), before it empties into the Pacific Ocean at the port at Kushiro. The lower reaches of the river form broad wetlands. The (13 kilometres (8.1 mi)), which was built roughly parallel to the Kushiro River, was completed in 1931 and flows south to the Pacific Ocean.