20th Division
- 20th (Light) Division
- 20th Air Division
- 20th Armored Division (United States)
- 20th Armoured Division (Greece)
- 20th Division (German Empire)
- 20th Division (Imperial Japanese Army)
- 20th Division (Spain)
- 20th Guards Motor Rifle Division
- 20th Infantry Division (Greece)
- 20th Infantry Division (India)
- 20th Infantry Division (Poland)
- 20th Infantry Division (Wehrmacht)
- 20th Infantry Division Friuli
- 20th Panzer Division (Wehrmacht)
- 20th Regiment (disambiguation)
- 20th Waffen Grenadier Division of the SS (1st Estonian)