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.

Lebanon County is a county in the Commonwealth of Pennsylvania, United States. As of the 2020 census, the population was 143,257. Its county seat is the city of Lebanon. It lies 72 miles northwest of Philadelphia, which is the nearest major city. The county is part of the South Central Pennsylvania region of the state.