The Tikchik River is a stream, 45 miles (72 km) long, in the U.S. state of Alaska. Beginning at Nishlik Lake in the Kuskokwim Mountains, it flows southeast into Tikchik Lake, 65 miles (105 km) north of Dillingham. Tikchik Lake empties into the Nuyakuk River, a tributary of the Nushagak River, which flows to Nushagak Bay, an arm of Bristol Bay.Water from Upnuk Lake flows about 10 miles (16 km) to join the river downstream of Nishlik Lake.