This study aims to examine whether perceived levels of job stress, burnout, and mental health are different according to demographic characteristics and working conditions and to investigate the direct and indirect effects of job stress and burnout on the mental health of medical faculty members. The study sample consists of 855 faculty members in 40 medical schools nationwide in the 2020 Burnout of Faculty Members of Medical Schools in Korea data with a grant from the Korean Association of Medical Colleges. This study employed structural equation modeling to construct causality among latent variables in addition to t-test, analysis of variance, and correlation coefficients for bivariate analyses. Perceived job stress, burnout, and mental health levels of medical faculty members showed significant group differences by demographic characteristics and working conditions. Job stress directly affected mental health (β=0.215, p<0.01) and indirectly affected mental health via burnout (β=0.493, p<0.001). Thus burnout significantly mediated the relationship between job stress and the mental health of medical faculty members. This study found that job stress has direct and indirect effects on the mental health of medical faculty members, and burnout partially mediated this relationship. Further studies need to intervene in job stress and burnout to prevent the adverse mental health of medical faculty members and to introduce proper measures to improve working conditions affecting job stress and burnout.