The 41st Regiment Massachusetts Volunteer Infantry was a three-year infantry regiment that served in the Union Army during the American Civil War. It was recruited as part of Governors Banks' and Andrew's recruitment drives to supply the union with a military force to hold and expand Union control of the lower Mississippi. In the late winter/early spring of 1863, it was converted to mounted infantry and later to cavalry. On its conversion in June 1863 at Port Hudson, it was disestablished and re-established as the 3rd Massachusetts Volunteer Cavalry.