The Grand Lodge and Library of the Ancient Free and Accepted Masons in Sioux Falls, South Dakota is a building from 1924.

[2] The National Register nomination describes its importance as "the purest example of Neo-classic style in Sioux Falls.

The combination of classic elements and internal structural innovations of the early twentieth century, such as steel doors and trim painted to resemble wood and a nine-ton glass floor, enhance the architectural importance of the structure.

"[3] The building has one of the largest Masonic libraries in the United States.

This article about a property in South Dakota on the National Register of Historic Places is a stub.