20th Regiment

20th Regiment may refer to:

Infantry regiments

 * 20th Infantry Regiment (Philippine Commonwealth)
 * 20th Infantry Regiment (United States)
 * 20th Pennsylvania Infantry
 * 20th Regiment Indiana Infantry
 * 20th Maine Regiment
 * 20th Maine Volunteer Infantry Regiment
 * 20th Regiment of Bengal Native Infantry
 * 20th Illinois Volunteer Infantry Regiment
 * 20th Wisconsin Volunteer Infantry Regiment
 * 20th Michigan Volunteer Infantry Regiment
 * 20th Iowa Volunteer Infantry Regiment
 * 20th Regiment Massachusetts Volunteer Infantry
 * Lancashire Fusiliers, formerly 20th Regiment of Foot

Other regiments

 * 20th Marine Regiment (United States)
 * 20th Field Regiment, Royal Canadian Artillery
 * 20th Hussars
 * 20th Surveillance and Target Acquisition Regiment, Royal Australian Artillery