Big Otter Creek is a waterway that empties into Lake Erie at Port Burwell, Ontario. It is 42 kilometres (26 mi) long, and the area of its drainage basin is 712 square kilometres (275 sq mi). The creek's headwaters are north of the Horseshoe Moraine, and its mouth is just west of the Long Point Conservation Area. Scenic bluffs line the valley as it passes through the moraine.