Quentin is an unincorporated community and census-designated place (CDP) in Lebanon County, Pennsylvania, United States. It was named after Quentin Roosevelt, youngest son of President Theodore Roosevelt. The population was 594 at the 2010 census, up from 529 at the 2000 census.
The town was originally named "Bismark", a local spelling of the name of Otto von Bismarck. In October 1920, the name was changed to honor Quentin Roosevelt, who was killed while flying as a fighter pilot during World War I.
Quentin is located in southern Lebanon County, in the northeast corner of West Cornwall Township. It is bordered to the east by the borough of Cornwall.
U.S. Route 322 forms the southwestern edge of the Quentin CDP; it leads west to Harrisburg, the state capital, and southeast to Ephrata in Lancaster County. Pennsylvania Route 72 runs through the eastern side of Quentin, leading north to Lebanon, the county seat, and south to Lancaster. Pennsylvania R