Millersburg is a borough in Dauphin County, Pennsylvania, United States. According to the US Census Bureau, the 2010 population declined to 2,557 people. The population was 2,562 at the 2000 census. It is part of the HarrisburgCarlisleMetropolitan Statistical Area. Millersburg is located on the east bank of the Susquehanna River at 403230N765726W / 40.54167N 76.95722W / 40.54167; -76.95722 (40.541676, -76.957283). According to the United States Census Bureau, the borough of Millersburg has a total area of 0.8 square miles (2.1km2), all of it land.