Upper Macungie Township is a township in Lehigh County, Pennsylvania. The population of Upper Macungie Township was 26,377 as of the 2020 U.S. census, making it the fourth fastest-growing municipality in Pennsylvania in terms of total population gain from 2010 to 2020. The township was created in 1832 when Macungie Township was divided into Upper and Lower Macungie townships. It is part of the Lehigh Valley metropolitan area, which had a population of 861,899 and was the 68th most populous metropolitan area in the U.S. as of the 2020 census.