TWR may mean:
- Tom Walkinshaw Racing, a racing team founded in 1976
- Trans World Radio, a multinational Christian evangelistic broadcaster
- Traveling wave reactor, a type of nuclear reactor that would convert fertile material into fissile fuel
- The Weekly Reader, an American weekly educational classroom magazine designed for children in grades Pre-K–12
- Tokyo Waterfront Area Rapid Transit, the operator of the Rinkai railway line in Tokyo, Japan
- Thrust-to-weight ratio, a dimensionless indicator of the performance of an engine or vehicle
- Time weighted return, a specific rate of return calculation method