12th Division may refer to:
- 12th Division (Australia)
- 12th Reserve Division (German Empire), a unit of the Imperial German Army in World War I
- 12th Infantry Division (Germany), a German military unit that fought during World War II
- 12th Mechanized Infantry Division (Greece), a Greek unit based at Alexandroupoli, Thrace
- 12th Infantry Division Sassari (Kingdom of Italy)
- 12th Indian Division – British Indian Army during World War I
- 12th Infantry Division (India)
- 12th Division (Imperial Japanese Army), was an infantry division in the Imperial Japanese Army
- 12th Division (North Korea), was a division of the Korean People's Army
- 12th Infantry Division (Pakistan), is a Pakistani Army infantry division currently based in Murree, Punjab
- 12th Infantry Division (Poland), was a tactical unit of the Polish Army in the interbellum period
- 12th Amurskaya Rifle Division, was a military formation of the Red Army during World War II
- 12th (Eastern) Division, was a division raised by the British Army during the First World War
- 12th (Eastern) Infantry Division, was a division raised by the British Army during the Second World War
- 12th Infantry Division (South Korea), infantry division of the South Korea Army
- 12th Division (United States), infantry division of the United States Army, active in 1918–1919
- Philippine Division (United States), also designated as the US 12th Infantry Division