Lost River
- Big Lost River
- Harrington, Quebec
- Little Lost River
- Losing stream
- Lost River (Bering Sea)
- Lost River (Cacapon River tributary)
- Lost River (California)
- Lost River (Clearwater River tributary)
- Lost River (Indiana)
- Lost River (Nett Lake)
- Lost River (New Hampshire)
- Lost River (Roseau River tributary)
- Lost River (Tamarac River tributary)
- Lost River (Thief River tributary)
- Lost River (film)
- Lost River Athletic Conference
- Lost River Cave
- Lost River Caverns
- Lost River Jr./Sr. High School
- Lost River State Forest
- Lost River Township, Martin County, Indiana
- Lost River, Idaho
- Lost River, Indiana
- Lost River, Kentucky
- Lost River, New South Wales
- Lost River, West Virginia
- Methow River
- Nowitna River
- Rural Municipality of Lost River No. 313
- The Lost River