This is a list of regiments from Missouri that fought in the Union Army during the American Civil War (1861–1865). The list of Missouri Confederate Civil War units is shown separately.
Long-Enlistment Infantry Regiments
1st Missouri Volunteer Infantry - Reorganized as batteries of 1st Missouri Lt Arty 2nd Missouri Volunteer Infantry 3rd Missouri Volunteer Infantry 3rd Missouri US Reserve Corps Infantry - "Turner Zouaves" 4th Missouri Volunteer Infantry 5th Missouri Volunteer Infantry 6th Missouri Volunteer Infantry - "Bates Guards" 7th Missouri Volunteer Infantry - "The Irish Regiment", "The Irish Seventh" 8th Missouri Volunteer Infantry - "American Zouaves" 9th Missouri Volunteer Infantry - "Washington Zouaves" 10th Missouri Volunteer Infantry 11th Missouri Volunteer Infantry 12th Missouri Volunteer Infantry 13th Missouri Volunteer Infantry Western Sharpshooters-14th Missouri Volunteer Infantry - (formerly) Birge's Western Sharpshooters (later 66th Illinois Volunteer Infantry Regiment (Western Sharpshooters)) 15th Missouri Volunteer Infantry 16th Missouri Volunteer Infantry - Failed to complete organization 17th Missouri Volunteer Infantry - "Western Turner Rifles" 18th Missouri Volunteer Infantry 19th Missouri Volunteer Infantry - Failed to complete organization 20th Missouri Volunteer Infantry - Failed to complete organization 21st Missouri Volunteer Infantry 22nd Missouri Volunteer Infantry 23rd Missouri Volunteer Infantry 24th Missouri Volunteer Infantry - The Lyon Legion 25th Missouri Volunteer Infantry 26th Missouri Volunteer Infantry 27th Missouri Volunteer Infantry 27th Missouri Volunteer Mounted Infantry 28th Missouri Volunteer Infantry - Failed to complete organization 29th Missouri Volunteer Infantry 30th Missouri Volunteer Infantry - "Shamrock Regiment" (second Missouri Irish Regiment) 31st Missouri Volunteer Infantry 32nd Missouri Volunteer Infantry 33rd Missouri Volunteer Infantry 34th Missouri Volunteer Infantry - Failed to complete organization 35th Missouri Volunteer Infantry 36th Missouri Volunteer Infantry 37th Missouri Volunteer Infantry - Failed to complete organization 38th Missouri Volunteer Infantry - Failed to complete organization 39th Missouri Volunteer Infantry 40th Missouri Volunteer Infantry 41st Missouri Volunteer Infantry 42nd Missouri Volunteer Infantry 43rd Missouri Volunteer Infantry 44th Missouri Volunteer Infantry 45th Missouri Volunteer Infantry 46th Missouri Volunteer Infantry 47th Missouri Volunteer Infantry 48th Missouri Volunteer Infantry 49th Missouri Volunteer Infantry 50th Missouri Volunteer Infantry 51st Missouri Volunteer Infantry 52nd Missouri Volunteer Infantry 53rd Missouri Volunteer Infantry 54th Missouri Volunteer Infantry 56th Missouri Volunteer Infantry
Short-Enlistment Infantry Regiments
1st Missouri Volunteer Infantry (3 Months, 1861) 2nd Missouri Volunteer Infantry (3 months, 1861) 3rd Missouri Volunteer Infantry (3 months, 1861) "Lyon's Fahnenwacht" (Lyon's Color Guard) 4th Missouri Volunteer Infantry (3 months, 1861) "Schwarze Jäger" (Black Hunters, aka Black Rifle Hunters) 5th Missouri Volunteer Infantry (3 months, 1861)
1st Northeast Regiment of Missouri Infantry, 1861
2nd Northeast Regiment of Missouri Infantry, 1861
1st Missouri, US Reserve Corps Infantry (3 months, 1861) 2nd Missouri, US Reserve Corps Infantry (3 months, 1861) 3rd Missouri, US Reserve Corps Infantry (3 months, 1861) "Turner-Zuaven" (Turner Zouaves) 4th Missouri, US Reserve Corps Infantry (3 months, 1861) 5th Missouri, US Reserve Corps Infantry (3 months, 1861)