St. Mary Basilica, formerly St. Mary's Cathedral, located in Natchez, Mississippi, United States, is a parish church in the Diocese of Jackson and Minor basilica of the Catholic Church. In 1979 it was listed under its former name as a contributing property in the Natchez On-Top-of-the-Hill Historic District on the National Register of Historic Places. The Basilica was dedicated to Mary, under the title Our Lady of Sorrows on December 25, 1843.