||In the given queer discourses in Taiwan’s cultural context, it is quite common to discern a taken-for-granted understanding of the emergence of same-sex sexual identity or the exclusion of same-sex sexual practices outside the family under the influence of capitalism. Narrowing the focus on such a presupposition, this thesis will painstakingly take on the gradual formation of the so-called “normal” sexual practices in terms of the transformation of bisexual practices within the family under the influence of capitalism. I intend to highlight the limited distinction of human sexuality within a framework of homosexual and heterosexual and the oppressive and coercive mechanism of present monogamous heterosexual family toward the individual by the juxtaposition of how bisexual practices might have been realized then in the polygamous family and have been engaged inside/outside the monogamous heterosexual family nowadays. The implication of such an understanding of the transformation of bisexual practices is that it provides a vantage point from which to interrogate the legitimacy of monogamous heterosexual family at the present time and offers a great intervention into current sexual politics on the family in terms of sexual citizenship. I argue it is the specific transformed process of the family in its structure, functions and the intimate relationships that we could reflexively think of the coercive mechanisms of a given normative sex/gender system and the monogamous heterosexual system and thus contributes to understanding the problems of sexual injustices and inequality at the present time.