This study is aims to illuminate democratic tendency in Post-modern dance during the Postwar Era, especially focused on its political and social aspects. In the 20th century, especially during the sixties, the whole art of America under the counter-cultural environment was consisted mainly of radical idea and emphasis on the sprit of experiment. Intrigued by the opportunity that improvisation afforded to invoke an entirely unanticipated organization of things and events, experimental groups throughout the 1960s and the 1970s(Post-modern dance era) borrowed from jazz and its principles for composing in performance. To illuminate democratic inclination with improvisation shown in Post-modern dance, such as San Francisco Dancers Workshop, Judson Dance Theater, New York Chamber Dance Group, Workgroup, Grand Union, Contact Improvisation group. Post-modern dance era, dance groups allowed performers to share in a process of making work collectively, and many times this process extended to include the audience as well. At the same time that Post-modern groups appropriated for Asian and African identity, sex role to democratic tendency. As a result, in these group's dance, dancers applied improvisation to represent democratic thoughts and become aware of racial and sexual identity as well as the value of human body. Post-modern dance become more and more extended their ideas techniques and democratic inclination.