Ro
- Roanoke River - Virginia, North Carolina
- Roaring River - Missouri
- Roaring River - North Carolina
- Roaring River - Tennessee
- Roaring Fork River - Colorado
- Robinson River - Virginia
- Rock Creek - Maryland, District of Columbia
- Rock Creek (Clear Creek) - Wyoming
- Rock Creek (Medicine Bow River) - Wyoming
- Rock River - Illinois, Wisconsin
- Rock River - Minnesota, Iowa
- Rock River - Vermont (northern)
- Rock River - Vermont (southern)
- Rockaway River - New Jersey
- Rockcastle River - Kentucky
- Rockfish River - Virginia
- Rocky Branch - New Hampshire
- Rocky River - Alaska
- Rocky River - Connecticut
- Rocky River - Michigan
- Rocky River - Ohio
- Rocky River - South Carolina
- Rocky River - Tennessee
- Roe River - Montana
- Roger Island River - Massachusetts
- Rogue River - Michigan
- Rogue River - Oregon
- Rolling Fork - Arkansas
- Rolling Fork Salt River - Kentucky
- Rondout Creek - New York
- Rooster River - Connecticut
- Root River - Minnesota
- Root River - Wisconsin (tributary of Des Plaines River)
- Root River - Wisconsin (tributary of Lake Michigan)
- Roseau River - Minnesota
- Rough River - Kentucky
- Row River - Oregon
- Rowley River - Massachusetts
- Royal River - Maine
Read more about this topic: List Of Rivers Of The United States: R