Barry Levinson’s film Wag the Dog(1997) is concerned with the technological transformation of American culture in the postmodernism which is isomorphic with the media culture of American society in the late twentieth century. By exploring three dualities illustrated in the film,this paper aims to show the insecure and uncertain categories of these oppositions under the dominant phenomena of this period: the media,so as to bring about the public’s ability to discern the postmodern world as well as a new ways of thinking and living.