15th Brigade
- 15 Squadron (disambiguation)
- 15th (Imperial Service) Cavalry Brigade
- 15th Army (disambiguation)
- 15th Brigade (Australia)
- 15th Brigade (Japan)
- 15th Division (disambiguation)
- 15th Group (disambiguation)
- 15th Infantry Brigade (Greece)
- 15th Infantry Brigade (Hungary)
- 15th Infantry Brigade (United Kingdom)
- 15th Mechanized Brigade (Romania)
- 15th Mounted Brigade (United Kingdom)
- 15th Regiment (disambiguation)
- 15th Separate Guards Motor Rifle Brigade
- 15th Sustainment Brigade (United States)
- 15th Wing (disambiguation)
- XV Brigade, Royal Horse Artillery
- XV Corps (disambiguation)
- XV International Brigade