<p>Interdisciplinary competence is recognized as a key outcome of interdisciplinary education; however, empirical research on how this competence is cultivated remains limited. Grounded in Astin’s Input-Environment-Outcome (I-E-O) model and Student Involvement Theory, this study investigates the direct and indirect effects of key components of the Interdisciplinary Educational Ecosystem, namely interdisciplinary curricula, student-centered teaching approaches, organizational support for communication and collaboration, and organizational support for innovation, on students’ interdisciplinary competence in Chinese research universities. Structural equation modelling results show that interdisciplinary curricula have both significant direct effects and positive indirect effects mediated by students’ curricular engagement. Student-centered teaching approaches do not exert direct effects, but their influence is mediated through curricular engagement. Organizational support for communication and collaboration exerts both direct and indirect positive influences, whereas support for innovation shows a more limited and selectively mediated impact. The study offers important implications for designing effective environments that support interdisciplinary education in higher education.</p>