This article describes the development and functions of the American presidential library. The presidential library mainly preserves the papers, records, memorabilia, and artifacts of a former president. The first presidental library was established by President Franklin D. Roosevelt in 1939. So far, there are 10 presidental libraries in the United States. The origination and the related statutes of the presidential library are discussed. Furthermore, the authority governing the presidential library, and its functions are described. Finally, two suggestions are presented.