The purpose of this study is to discover the role of women in Eugene O'Neill's plays. I particular, we will examine the following plays : Beyond the Horizon, The Hairy Ape and Desire Under the Elms. These plays of O'Neill are nearly all concerned with the impelling, inscrutable force, behind women's lives. The playwright, always interested in Nietzsche's tragic thought, used Nietzschean Dionysian and Apollonian duality to make his characters in plays. Under the charm of the Dionysian, not only is the union between people reaffirmed, but nature, which has become alienated, hostile or subjugated, celebrates once more her reconciliation with her lost child, humanity. On the other hand, the Apollonian is the terrible image of the world fading away charmingly. Various studies and critical approaches to O'Neill have examined the conflict between life and death and the problems of salvation, belonging and identity. O'Neill's plays can be classified into two,"female" points of view. One is the idealist in whom we find dreams, lofty ideals, harmony, regeneration and redemption. The other is the actualist who, being imprudent, demolishes the social order and brings about trouble, confrontation and self-destructive struggle.