In the context of globalisation, fostering secondary vocational students with a craftsman spirit is crucial for industrial transformation and addressing contemporary needs. Based on social cognitive career theory, this study explores the mechanism through which professional ability influences craftsman spirit among secondary vocational students as well as the mediating role of career decision-making self-efficacy and the moderating role of goal realisation in this process. We tested our hypotheses using data gathered from 650 secondary vocational students; the results suggested that secondary vocational students' professional ability have a significant positive impact on the craftsman spirit. We also found that career decision-making self-efficacy partially mediates the effect of professional ability on craftsman spirit. Further, we found that self-concordant goal realisation positively moderates the relationship between professional ability and career decision-making self-efficacy. We offer theoretical guidance and practical implications for cultivating craftsman spirit among students in secondary vocational institutions.