St. Mary's Assumption Church may refer to:
- St. Mary's Assumption Church, Sławno
- St. Mary's Assumption Church (Cottonport, Louisiana), listed on the National Register of Historic Places in Avoyelles Parish, Louisiana
- St. Mary's Assumption Church (New Orleans, Louisiana), listed on the National Register of Historic Places in Orleans Parish, Louisiana
- St. Mary's Assumption Catholic Church, listed on the National Register of Historic Places in Iron County, Michigan