51st Brigade
51st Brigade or 51st Infantry Brigade may refer to:
Belarus
India
- 51st Indian Brigade of the British Indian Army in the First World War
- 51st Indian Infantry Brigade of the British Indian Army in the Second World War
Soviet Union
Ukraine
United Kingdom
Artillery units
- 51st (Lancashire and Cumberland) Brigade, Royal Field Artillery
- 51st (Westmorland and Cumberland) Brigade, Royal Field Artillery
- 51st (London) Anti-Aircraft Brigade, Royal Garrison Artillery
- 51st (Cornwall and Warwickshire) Medium Brigade, Royal Garrison Artillery
- 51st (Midland) Medium Brigade, Royal Garrison Artillery