Shawnigan Creek Weir is a water-control structure located on Shawnigan Creek, approximately 0. 5 kilometres downstream from the outlet of Shawnigan Lake on southern Vancouver Island.

The weir sits within the Cowichan Valley Regional District's Electoral Area B, near the village of Shawnigan Lake. The structure lies at the lower end of a study area used for flood monitoring and floodplain analysis of Shawnigan Lake and its outlet creek.

Shawnigan Creek drains a watershed of roughly 71 km², flowing north and eventually entering the ocean at Mill Bay via Saanich Inlet.