Carnegie Free Library is a historic Carnegie library building located at Connellsville, Fayette County, Pennsylvania. It was designed and built in 1901, with funds partly provided by the philanthropist Andrew Carnegie. Carnegie provided $50,000 toward the construction of the Connellsville library. The grant was commissioned by Carnegie on April 22, 1899; it was the 13th library that he commissioned in America. It is a two-story Ohio buff stone structure with basement in the Italian Renaissance Revival style. The exterior features a terra cotta cornice and red Spanish tile roof. It measures by .
It was added to the National Register of Historic Places in 1981.