The 11th New Hampshire Volunteer Regiment was a Union army infantry regiment that participated in the American Civil War. It was raised in the New England state of New Hampshire, serving from October 4, 1862, to June 4, 1865. On September 2, 1862, the regiment was organized and mustered in at Concord, New Hampshire. Among its notable officers was Walter Harriman, a future Governor of New Hampshire. The regiment lost during its term of service 5 officers and 140 enlisted men killed and mortally wounded, and 1 officer and 151 enlisted men by disease, for a total of 297 fatalities.