Background <p>Resilience, career decision self-efficacy, and career adaptability are university students’ important personal resources in coping with the challenges they face in the career development process. No longitudinal studies have examined the relationships and possible mediating mechanisms between these resources. Therefore, based on career construction theory, the current study aims to explore the longitudinal relationships between resilience, career decision self-efficacy, and career adaptability and to examine if career decision self-efficacy has a mediating role in the relationship between resilience and career adaptability.</p> Methods <p>The participants of the study consisted of 376 (239 female, 137 male; M_Age=20.87, SD_Age =1.83) university students who responded to the online survey in both times (T1 and T2). Data were collected through self-report questionnaires and analyzed using a cross-lagged panel model.</p> Results <p>The findings of the study showed that while resilience at T1 significantly predicted career decision self-efficacy at T2, career decision self-efficacy at T1 significantly predicted career adaptability at T2 in university students. The results of the cross-lagged panel model also showed that career decision self-efficacy played an important mediating role in the longitudinal relationship between resilience and career adaptability.</p> Conclusions <p>This longitudinal study is believed to advance research based on career construction theory by contributing to a better understanding of the longitudinal relationship between resilience and career adaptability through mediating mechanisms. The study also emphasizes the importance of strengthening university students’ personal resources in their career development process. The findings of the study indicate important implications for both theoretical and career counseling practices.</p>