RSR, a three letter acronym that may mean:
- Radio Suisse Romande the Swiss French public service radio group
- Railway Safety Regulator, an agency of the South African government
- Relative survival rate
- Reverie Sound Revue, a Canadian band
- Former international license plate code for Southern Rhodesia
- Rock Structure Rating
- Rochester and Southern Railroad
- Romanian Socialist Republic or Republica Socialistă România, the name of Communist Romania from 1965 to 1989
- Ronald Suresh Roberts, a biographer and columnist living in South Africa
- Rotary Scout Reservation, a Boy Scout camp in upstate New York
- RSR (spyplane), a Russian supersonic surveillance aircraft
- RSR ("RennSport Rennwagen") designates race versions of the Porsche 911, e.g. the 1970s Carrera RSR or the 2000s GT3 RSR
- Red Storm Rising, techno-thriller novel by Tom Clancy and Larry Bond.