<p>Within the context of Chinese higher education, <i>Shi-men</i> – an informal supervisory structure– is widely employed, yet remains under-theorised in the academic literature. While previous research has examined the classification, cultural characteristics and general influence of Shi-men, limited attention has been paid to its internal operational logic and the action strategies employed by students. Addressing this gap, the present research employs Giddens’s structuration theory (1984) and the Chinese concept of <i>guanxi</i>, to explore the operational logic of Shi-men, the tensions between Shi-men structure and graduate students’ agency and how students exercise agency to participate in and negotiate with Shi-men. Drawing on semi-structured interviews with 47 graduate students from 28 Project 985 universities, the findings reveal that the operational logics of Shi-men is shaped by its functions. These functions govern the mobilisation of rules and resources in daily practices, thereby developing three patterns of Shi-men: family-like, enterprise-like and workshop-like. Graduate students encounter three key tensions within Shi-men, these are authority/autonomy, moral obligation/instrumental interests, and role expectation/self-aspiration. In addition, they adopt strategies to participate in, negotiate with and reproduce Shi-men through complete compliance, strategic accommodation, implicit resistance and overt withdrawal. By adopting Giddens’s structuration theory and the Chinese concept of guanxi, the findings extend international studies on graduate education by constructing structure-guanxi-agency dynamics to a non-Western context, while also calling on institutions and faculty to recognise both the developmental potential and the risks of such informal structures.</p>