Lionville-Marchwood is a census-designated place (CDP) in Uwchlan Township, Chester County, Pennsylvania, United States. The population was 6,298 at the 2000 census. Lionville is bisected by two major local highways, PA 100 and PA 113. The area contains residential neighborhoods, hotels, restaurants, and other businesses. While the census designation is Lionville-Marchwood, Lionville is officially the village that is part of Uwchlan Township.