The Sheslay River is a tributary of the Inklin River in northwest part of the province of British Columbia, Canada. It joins the Nahlin River to form the Inklin River, one of the main tributaries of the Taku River. The lower Sheslay River marks the boundary between the Taku Plateau and the Nahlin Plateau. Its mouth at the Nahlin River marks the junction of the Taku, Nahlin, and Kawdy Plateaus. All three of these are part of the larger Stikine Plateau region.