After the  collapse of the U.S.S.R, NATO not only didn’t collapse but extended in it’s mission and geography. This article through the survey ot theorize and approaches which have tried to describe this phenomena, is analyzing the role of American hegemony, NATO as a valuable asset for the U.S, has a considerable role in the consolidation of American hegemony, and continuity of American influence in Europe. it gives America necessary means to impact on the regional and World events and Trends. The U.S has tried to strength this transatlantic organization and through which it prevents the rise of  similar, but independent organizations in the Europe. Accordingly NATO has found further role in the security environment of West Europe, Est Europe and other neiboring regions and is becoming effective in the consolidation of American hegemony.