This essay deals with the American historiography in the decades after the Second World War up to 1980s. In these decades there were a number of new developments: the first is the rise and fall of the Neoconsevertist historiography; the second is the appearance of historiographic interpretation of the New Leftists; the third is the arrival of the New-sociological historiography; the last is the trend of various new histories, including new economic political, and urban histories, and, the extension of traditional historiography. The author points out that owing to the strengthening of American professional historiography, what Croce had said, "every history is a contemporary history" becomes truer; and , American historians are subject to create new interpretations in the future decades.