OPC may refer to:
- Computing
- OLE for process control
- OPC Foundation, a related consortium
- Open Packaging Conventions
- Operations Planning and Control, renamed to IBM Tivoli Workload Scheduler (TWS)
- Optimized Power Control, a method to adjust laser power when writing optical media.
- Object Linking and Embedding for Process Control (OPC), in MPDV
- Architecture and engineering
- Optical proximity correction
- Optimized Power Control (or Optimum Power Calibration), a function of a CD or DVD writer
- Ordinary Portland cement
- Organic Photoconductor, an element used for, among other applications, photocopier drums.
- Natural sciences
- Ocean Prediction Center
- Oligomeric proanthocyanidin
- Social matters, politics and government
- Office of Policy Coordination, a secret U.S. government unit, 1948-1951
- Office of the Privacy Commissioner of Canada
- Overseas Press Club
- Oodua Peoples Congress, militant Yoruba nationalist organization situated in Nigeria
- (Federal) Office for the Protection of the Constitution, a translation of the German name Bundesamt für Verfassungsschutz
- Orthodox Presbyterian Church
- Online Party of Canada
- Other
- Ontario Police College
- Ontario Pioneer Camp, in Huntsville, Ontario, Canada
- Orthotic Prosthetic Center
- O-Pee-Chee, a Canadian sports card company
- OPC, Opel Performance Center a subsidiary of car manufacturer Opel