Prince William County Courthouse is a historic courthouse located at Manassas, Prince William County, Virginia. It was built in 1892-1893, and is a two-story, Romanesque style polychromatic brick building. It measures 52 feet by 60 feet and has a hipped roof. The front facade is symmetrical and features a projecting central bay forming a three-story clock tower topped with a cupola. The building was restored in 2000-2001. The county government moved to the building from the Brentsville Courthouse and Jail, and the building continued to be actively used as a county courthouse until 1984.
It was added to the National Register of Historic Places in 2004.