<p>Graduate student socialization is a critical area of research, given its profound implications for future career trajectories of students and the overall quality of graduate programs. This study integrates the graduate student socialization framework with self-formation theory to examine Chinese graduate students’ academic socialization process. Drawing from a quantitative analysis of 19,478 graduate students and a subsequent qualitative analysis of 23 participants, the findings reveal that students’ perceptions of the learning environment are positively associated with their learning outcomes, with student engagement mediating this relationship. Additionally, graduate students demonstrate reflexive agency, navigating their interactions with contextual factors to construct a multiple-coded self—a synthesis of their inner self and social self shaped by interpersonal, disciplinary, institutional, and societal systems. The study concludes by offering practical implications for higher education institutions and graduate programs to facilitate graduate students’ academic socialization.</p>