St. Stanislaus Kostka Church in Pittsburgh, Pennsylvania, referred to in Polish as Kościół Świętego Stanisława Kostki is a historic church of the Roman Catholic Diocese of Pittsburgh. Located in the Strip District in Pittsburgh, Pennsylvania, United States, it is a prime example of the so-called 'Polish Cathedral' style of churches. It is known also as 21st and Smallman Street Church. It is listed on the U.S. National Register of Historic Places.