This study contributes evidence on the impact of developmental advising using a national sample of students in the undergraduate clinical medicine program in China (n = 122,932). Using a combination of instrumental variable regression and structural equation modeling, the study explored beyond low-touch informative intervention and fully presented how developmental advising makes effects. A significantly positive advising effect on both academic and non-academic indicators was found, and it varies by the students' demographic features, family backgrounds, and pre-college experiences, suggesting its potential to address achievement gaps across students from different backgrounds. In addition, the mediating roles of self-efficacy and learning engagement that enable advising to impact academic improvement were verified, shedding light on how developmental advising impacts students' development.