New Tripoli (/trɪˈpoʊli/ trih-POH-lee) is an unincorporated community and census-designated place (CDP) in Lynn Township in Lehigh County, Pennsylvania. As of the 2020 census, the population was 840. New Tripoli is part of the Lehigh Valley, which had a population of 861,899 and was the 68th most populous metropolitan area in the U.S. as of the 2020 census.