PWR can refer to:
- Pratt & Whitney Rocketdyne Engineering
- Power, a common abbreviation in Electronics.
- Politechnika Wroclawska, or Wroclaw University of Technology
- Pairwise Rankings, a common ranking system used to achieve collegiete sports seeding
- Pressurized water reactor, a type of nuclear power reactor
- PAHO/WHO Representation, the staff and facilities associated with a regional office of the Pan-American Health Organization
- The Preston and Wyre Railway, a historic railway company in Lancashire, England