| Unit Name: | 3rd West Virginia Infantry Regiment |
| Dates: | June, 1861 to January 26, 1864 |
| Country: | United States |
| Allegiance: | Union |
| Branch: | Infantry |
| Battles: | American Civil War 1861: Battle of Cheat Mountain 1862: Battle of McDowell, Battle of Cross Keys, Battle of Cedar Mountain, Battle of Groveton, Second Battle of Bull Run 1863: Battle of White Sulphur Springs, Battle of Droop Mountain |
| Commander1: | Francis Thompson |
| Commander1 Label: | Lt. Colonel |
The 3rd West Virginia Infantry Regiment was an infantry regiment that served in the Union Army during the American Civil War. It fought in Virginia and West Virginia. On May 23, 1863, it was converted to a mounted infantry by Brigadier General William W. Averell. The regiment was immediately sent to a camp for instruction and supplied. On January 26, 1864, it was reorganized as the 6th West Virginia Volunteer Cavalry Regiment.
The 3rd West Virginia Infantry Regiment fought at the Battle of McDowell on May, 1862 and the Battle of Cross Keys, June 8, 1862, under LTC Francis W. Thompson, part of BG Robert Milroy's Brigade made up of 5 Virginia regiments loyal to the Union (units which later were designated West Virginian) and 1 Ohio regiment and 3 Ohio artillery batteries. The regiment was converted to the 6th West Virginia Cavalry Regiment on January 26, 1864.
Richard W. Blue was an officer in it.