The unconventional surnaming practice of “adopting the mother’s surname” (hereafter AMS) has been an emerging phenomenon in mainland China in recent decades. However, little research has been conducted into this issue. This study analyzes AMS by examining the causes and patterns of the phenomenon as well as the profound values behind it. The following questions are addressed: What causes the intention for AMS? How do current Chinese families actually make surname decisions for their children? Can AMS be ethically justified in terms of Confucian familism? The research adopted a qualitative method and materials for analysis were collected mainly from three sources: semi-structured in-depth interviews, judicial judgments, and a self-initiated survey. With regard to the causes, analysis suggests that two key factors that influence the intention for AMS. First, the changes in the family structure—specifically the emergence of the 4-2-1 structure resulting in a crisis of family inheritance represented by the surname. Meanwhile, the motivation of family continuity and surname inheritance made the surname of the third-generation children matter. Second, women’s status has increased women’s participation and power in children’s surname decision making, which in turn strengthen the intention for AMS. Next, based on interview cases, I distinguish the following three patterns of family decision making with regard to AMS in order to gain a better understanding of how family decisions are actually made to achieve AMS: the concerns-driven pattern, the agreement-harmony pattern, and the conflict pattern. Finally, I challenge the conventional view that Confucian familism acts as the main obstacle to the implementation of AMS and argue that AMS can be ethically defended in terms of the central values of Confucian familism and can be regarded as a new practice of filial piety.

In addition, AMS is examined not just within the family, but also in the broader social and political arena: “adopting the mother’s surname” should be understood not only as a consequence of the one-child policy, but also as having implications for future policy making that seeks to bring about gender equality.