The Mills County Courthouse, built in 1913, is an historic three-story Classical Revival-style courthouse building located at 1011 Fourth Street in Goldthwaite, Texas. Designed by San Antonio architect Henry Truman Phelps (1871–1944), it replaced the first courthouse built in 1890, which burned in 1912. The three-story building, made of brick with a cast stone basement, is the most prominent building in Goldthwaite. On November 8, 2000, it was added to the National Register of Historic Places.