BACKGROUND: Under the combined influence of the aftermath of the epidemic and aging, the shortage of health workforce has become increasingly serious across the globe, posing constraints to the achievement of Universal Health Coverage. Improving the professional identity of medical students can ensure a steady supply of potential medical workers, which can mitigate the shortage of medical workers. This study focuses on sad news about medical workers' arduousness, a dominant news type in public crises, and examines how it affects medical students' professional identity, which is regarded to be important in the development of medical education and public health. METHODS: This study employed a paper-and-pencil survey and recruited 1441 medical students in a Chinese university. Structural equation modeling (SEM) analysis with SmartPLS 3.0 was used to analyze the data. RESULTS: The results reveal that media stories have multi-layered impacts on medical students' professional identity. Their exposure of sad news about medical workers' arduousness not only has direct impacts on professional identity, but also exerts indirect impacts via the provision of online emotional support. CONCLUSION: This study has both theoretical and practical implications. In theory, the findings highlight the importance of media stories in the construction of professional identity and propose a theoretical framework for explaining the impacts of sad news exposure. In practice, this study contributes to the improvement of medical education, hospital management and public health governance in the digital age.