Butler Historic District is a national historic district located at Butler, Butler County, Pennsylvania. The district includes 128 contributing buildings, 1 contributing site, and 4 contributing objects in the central business district of Butler. It includes primarily commercial and institutional buildings, with some residential buildings, built between about 1828 and 1952 in a number of popular architectural styles including Late Victorian. Notable buildings include the City Hall, former U.S. Post Office (1912), Koch Building (c. 1910), T.W. Phillips Co. Office Building, Masonic Temple (1910), Butler High School (1917), Butler YMCA (1895), Butler YMCA (1913), First Evangelical Lutheran Church (1897), St. Andrews United Presbyterian Church (c. 1900), John Quincy Adams Kennedy House (c. 1884), St. Mark's Evangelical Lutheran Church and School (1952, 1925), First Baptist Church (1914), St. Paul's Roman Catholic Church (1909), and Butler Savings and Trust (1925). The contributing site is the Diamond, that contains the contributing objects including the Soldiers and Sailors Monument (1894). Located in the district and listed separately are the Butler County National Bank, the Sen. Walter Lowrie House, and the Butler County Courthouse.
It was listed on the National Register of Historic Places in 1976.