The Leo Ellis Post #22, American Legion Building is a historic American Legion building located at 804 Grant St. in Princeton, Mercer County, Missouri. It was built in 1935, and is a rectangular reinforced concrete structure faced in brick. It measures 30 feet by 32 feet, and features a crenelated parapet is capped by pre-formed concrete blocks.

It was added to the National Register of Historic Places in 1996.