RIR may mean:
- Real Illusions: Reflections, an album by American guitarist Steve Vai
- Recordable Incident Rate
- Reduction In Recruitment, a type of foreign labor certification program by the United States Department of Labor that preceded PERM program
- Rock in Rio
- Regional Internet registries, nonprofit corporations that administer and register Internet Protocol (IP) address space and Autonomous Systems (AS)
- Rhode Island Red, a breed of chicken
- Richmond International Raceway
- Riverside International Raceway
- Riverside (Rubidoux) Airport
- Royal Irish Regiment, either:
- Royal Irish Regiment (1684-1922)
- The Royal Irish Regiment (27th (Inniskilling) 83rd and 87th and Ulster Defence Regiment) (formed 1992)
- Rush in Rio, a live album by Canadian band Rush