The church was built in 1880-81 of brick with stone trim, and combines
Italianate,
Romanesque, and Classical elements. It features a high entrance porch, a turret with conical roof on the north wall, a square
bell tower at the northeast corner, a large
rose window in the main façade, and a variety of decorative brickwork. It was the first church in Maryland, and among the first in the nation, founded and built specifically for
Italian immigrants. The church was designed by Baltimore architect
E. Francis Baldwin. St. Leo's Church was listed on the
National Register of Historic Places in 1983. It houses an 1881 historic
Niemann pipe organ. The organ was played in recital during the Organ Historical Society Convention in July 2024. == Gallery ==