This paper aims to study the relation between enlightenment and sex revealed in Dialektik der Aufklarung written by Th. W. Adorno and M. Horkheimer. They insisted that Western modern spirit of enlightenment and its principle had a significant effect on sex awareness. According to them, we can summarize the characteristic of enlightenment as follows. First of all, enlightenment reveals the human superiority. Second, enlightenment aims at the unified system. Thus finally enlightenment excludes the incommensurable and enforces the uniformity. Now they regards mythology and enlightenment as equal. They insists that mythology is also the part of the enlightenment of western thought aims at ruling as a kind of rational systematization. They gave an amplification of their thoughts through Homer`s Odyssey. The main character, Odysseus is the embodiment of the enlightened citizen, that is the modern individual in this work. And also we can recognize that the consistent strategy of enlightenment is applied to the problem of sex through his contract with women like Penelope(Penelopeia) and Circe(Kirke). Applying enlightenment to whole western civilization as well as to mythology, they are able to make the sadistic heroine, Juliet(Juliette) a legitimate child of enlightenment. Finally we can treat Sade, the critic of enlightenment and Kant, the zenith figure of enlightenment in one same direction, without discrimination. Through holding up true mirror to the last terminus of enlightenment which purged the romantic love and believed in science thoroughly, Sade`s work clearly shows not the light of enlightenment but the negative, back side of enlightenment. Thus we can realize to what self-destruction the enlightenment as the domination general leads in the realm of sex.