CSIR may refer to:
- Organizations
- Council for Scientific and Industrial Research, an earlier name for the Commonwealth Scientific and Industrial Research Organisation, Australia between the years 1926 and 1949
- Council for Scientific and Industrial Research – Ghana
- Council for Scientific and Industrial Research, South Africa
- Council of Scientific and Industrial Research, India
- Italian Expeditionary Corps in Russia, or Corpo di Spedizione Italiano in Russia
- Technology
- Channel state information at the receiver
- Medicine
- Cross-sectional Interventional radiology