This study examines the impact of high-impact practices (HIPs) on non-cognitive skill development among vocational college students, a relatively understudied area. Using data collected from 7274 students across three vocational colleges in China in 2022, this study employs a cross-sectional survey design and applies advanced methods such as Coarsened Exact Matching (CEM) and Structural Equation Modelling (SEM) to confirm the significant positive effects of HIPs on non-cognitive skills including communication, problem-solving and innovation among vocational college students. The study also reveals important differences across groups, showing that students from vocational high schools, Han ethnicity and higher academic ranks benefit most. Crucially, teacher-student and student-student interactions are identified as key mediators that strengthen HIPs' impact. These findings challenge traditional views of vocational education and highlight the value of HIPs in fostering well-rounded student development. The results offer valuable guidance for policymakers and educators to integrate HIPs into vocational curricula, improving graduates' employability and adaptability. This research provides fresh insights and a strategic framework for advancing vocational education reform in China and beyond.