Bridging the skills gap between labour market demands and graduate preparedness is vital for the sustainable development of China’s Higher Vocational Education. Outcome-Based Education (OBE) has emerged as a promising approach, yet empirical evidence remains limited on how its core components contribute to competence development in specialised programs such as Cross-Border E-Commerce (CBEC). This study examines the relationships among intended learning outcomes, project-based learning, and assessment strategies, and their individual and combined effects on graduate competence in public higher vocational colleges (PHVCs) in China.