West Mifflin is a borough in Allegheny County, Pennsylvania, United States, located southeast of downtown Pittsburgh. The population was 20,313 at the 2010 census. It is named after Thomas Mifflin, 1st Governor of Pennsylvania, signer of the United States Constitution, and 1st Quartermaster General of the United States Army. Although the borough is heavily residential, it is home to one of America's oldest traditional amusement parks, Kennywood Park; the fourth largest shopping mall in the region, Century III; advanced naval nuclear propulsion technology research and development facility, Bettis Atomic Power Laboratory; monorail manufacturer Bombardier; US Steel's Irvin Plant; Community College of Allegheny County's South Campus; the Allegheny County Airport; and various other businesses and industries.
The West Mifflin Area School District is the public education provider for the borough. The district operates the following seven schools: the Early Childhood Education Center, Clara Barton Elementary, Homeville Elementary, New England Elementary, New Emerson Elementary, West Mifflin Area Middle School, and West Mifflin Area High School. Although the district bears the borough's name, it also provides PreSchool-12 education to the residents of Whitaker and high school education to a number of students residing in Duquesne.