Smithsonian American Latino Museum Act - Establishes a museum to be known as the Smithsonian American Latino Museum in the Smithsonian Institution.

Designates the Arts and Industries Building of the Smithsonian Institution, which is located on the National Mall in Washington, DC, including a new underground annex facility, as the location of the Museum.

Authorizes the Board of Regents of the Smithsonian Institution to plan and construct the Museum and to prepare a plan of action for the Museum.

Directs the Secretary of the Interior and the Board of Regents to enter into an agreement that allows for the construction of the underground annex facility by the Board in a manner that is harmonious with, and protects the open space and visual sight lines of, the National Mall.