Flat River may refer to:
- Flat River (Northwest Territories), a tributary of the South Nahanni River
- Flat River (Louisiana)
- Flat River (Missouri), a tributary of the Big River
- Flat River (Michigan)
- Flat River (North Carolina)
- Flat River (South Branch Pawtuxet River), a river in Kent County, Rhode Island
- Flat River (Wood River), a river in Kent and Washington County, Rhode Island
- Flat River, Missouri, the former name of Park Hills, Missouri
|This disambiguation page lists articles associated with the title Flat River.
If an internal link led you here, you may wish to change the link to point directly to the intended article.