The paper gives a brief introduce to big data firstly, then discusses the usage practice of big data prompted by America, there are as followings: government leads and whole people mobilize so as to abet the research and development of big data; non-mercantilism organization and education institute expand public service making use of big data actively; the library area responds actively, researches and attempts using big data. Lastly, based on these, the paper analyzes the beneficial references for our country brought by American experiences with the view of library.