The acronym WSI may refer to:

  • World Sindhi Institute - a human rights organization based in Washington DC, United States
  • Wafer-scale integration - a future silicon chip design for super computers
  • Wall Street Institute - multinational English-instruction school
  • Web Services Interoperability - Organization (WS-I), computer industry consortium
  • Western Sydney Institute of TAFE - college institute in New South Wales
  • Winter Soldier Investigation - media event on war crimes resulting from United States policies in the Vietnam War
  • Wojskowe Służby Informacyjne - Poland's former Military Intelligence Services
  • World Security Institute - think-tank for independent research and journalism on global affairs
  • Weather Stress Index - a relative measure of weather conditions
  • Weather Services International - a subsidiary of The Weather Channel, specializes in weather data and software.
  • Wrimare School Inc. - a Private school in Obando, Bulacan, Philippines.