20th Battalion may refer to:
20th Battalion (Australia), a World War I ANZAC battalion 2/20th Battalion (Australia), a World War II Australian infantry battalion 20th (Central Ontario) Battalion, CEF, a World War I battalion for the Canadian Corps 20th Battalion, London Regiment (Blackheath and Woolwich) 20th Battalion (New Zealand), a World War II infantry battalion
See also 20th Brigade (disambiguation) 20th Division (disambiguation) 20th Regiment (disambiguation) 20th Special Forces Group, a US Army National Guard group 20 Squadron (disambiguation) XX Corps (disambiguation)