This research aims to reconstruct the legal institution of marriage by examining the development of marriage law in Taiwan. It explores how the concept of marriage has been reshaped by principles of autonomy and caring relationships, and seeks to propose how marriage law might be reformed in Taiwan in the future. The landmark Constitutional Court Interpretation No. 748 in 2017 legalized same-sex marriage, marking a pivotal moment in the rule of law in Taiwan. This decision opened the “Taiwan model” of marriage reform, an approach that integrates judicial leadership, legislative action, and insights from feminist and queer theories. Following Interpretation No. 748, the Court issued Interpretation No. 791 in 2020, which decriminalized adultery and reinforced constitutional protections for the right to sexual autonomy. This, in turn, weakened the traditional responsibilities associated with marriage and further redefined it as a relationship grounded in intimacy, rather than procreation or sexual exclusivity. Together, these legal developments reflect a significant departure from the traditional, heteronormative model of marriage toward one rooted in autonomy and caregiving relationships. Thus, the legalization of same-sex marriage in Taiwan is not merely a matter of inclusion, but signals a deeper normative transformation of the institution of marriage itself. Increasingly, marriage in Taiwan is viewed as a flexible, welfare-oriented institution capable of accommodating diverse and care-based relationships. By reimagining marriage and family through the lens of autonomy and care, this research aims to contribute to future directions in the restructuring of marriage law in Taiwan.