| Shashiskau River | |
| Pushpin Map: | Canada Ontario |
| Pushpin Map Caption: | Location of the mouth of the Shashiskau River in Ontario |
| Subdivision Type1: | Country |
| Subdivision Name1: | Canada |
| Subdivision Type2: | Province |
| Subdivision Name2: | Ontario |
| Subdivision Type3: | Region |
| Subdivision Name3: | Northeastern Ontario |
| Subdivision Type4: | District |
| Subdivision Name4: | Cochrane |
| Source1: | Unnamed lake |
| Source1 Coordinates: | 50.2106°N -80.0858°W |
| Source1 Elevation: | 283m (928feet) |
| Mouth: | Kesagami River |
| Mouth Coordinates: | 50.9339°N -79.7819°W |
| Mouth Elevation: | 10m (30feet) |
| River System: | James Bay drainage basin |
| Tributaries Right: | Little Shashiskau River |
The Shashiskau River is a river in northern Cochrane District in Northeastern Ontario, Canada.[1] It is part of the James Bay drainage basin, and is a right tributary of the Kesagami River.
The river begins at an unnamed lake in the Shashiskau Hills and adjacent to Kesagami Lake and flows north through Shashiskau Lake, where it takes in the right tributary Little Shashiskau River. It continues north, turns northeast, takes in the right tributary Harvey Creek, and reaches its mouth at the Kesagami River. The Kesagami River flows via the Harricana River to James Bay.