Lemoyne is a borough in Cumberland County, Pennsylvania, United States, which lies across the Susquehanna River from Harrisburg, Pennsylvania's capital. It is part of the Harrisburg–Carlisle metropolitan statistical area. Lemoyne was incorporated as a borough on May 23, 1905. As of the 2020 census, the borough population was 4,659. Lemoyne is served by Interstate 83 and U.S. Routes 11/15. Lemoyne is a part of the West Shore School District.