The Knife River is a tributary of the Missouri River in the US state of North Dakota.
Knife River may also refer to:
Rivers
- Knife River (Lake Superior), a tributary of Lake Superior, in Minnesota, US
- Knife River (Snake River tributary), in Minnesota, US
- Knife River (Minnesota–Ontario), US and Canada
- North Knife River and South Knife River, Manitoba, Canada; see List of rivers of the Americas by coastline § Arctic Ocean coast
Places
Other
- Knife River Indian Villages National Historic Site, North Dakota
- Knife River Corporation, a construction materials company owned by MDU Resources