St. Cornelia's Episcopal Church is a historic church on the Lower Sioux Indian Reservation near Morton, Minnesota, United States. It was built 1889–91 for a Dakota congregation returning after years of exile from Minnesota following the Dakota War of 1862. It is also an example of the Episcopal missionary work among Native Americans and fine Gothic Revival church construction under Bishop Henry Benjamin Whipple (1822–1901). St. Cornelia's was added to the National Register of Historic Places in 1979. It was listed for having state-level significance in architecture, exploration/settlement, and religion.