Jerome is a census-designated place (CDP) in Somerset County, Pennsylvania, United States. The population was 779 as of 2010. It is part of the Johnstown, Pennsylvania, Metropolitan Statistical Area. Jerome is part of the municipality of Conemaugh Township, Somerset County, Pennsylvania, as are the nearby towns of Davidsville, Thomas Mills, Tire Hill, Seanor, Hiyasota and part of Holsopple.