45th Division may refer to:
Infantry divisions 45th Airborne Division, People's Republic of China 45th Infantry Division (France) 45th Reserve Division (German Empire) 45th Infantry Division (Wehrmacht), Germany 45th Infantry Division (Russian Empire) 45th Guards Rifle Division, Soviet Union, later the 45th Guards Motor Rifle Division 45th Rifle Division, Soviet Union 45th Division (Spain) 45th (2nd Wessex) Division, United Kingdom 45th Infantry Division (United Kingdom) 45th Infantry Division (United States)
Armoured divisions 45th Guards Tank Training Division, Soviet Union
Aviation divisions 45th Air Division, United States
See also List of military divisions by number 45th Army (disambiguation) 45th Brigade (disambiguation) 45th Regiment (disambiguation) 45th Squadron (disambiguation)