Objective To explore the mediating role of regulatory emotional self-efficacy between psychological quality and depression in graduate students of military medical college. Methods A cluster sampling survey was conducted among 485 military medical college graduate students using psychological quality questionnaire for medical master (PQQMM), regulatory emotional self-efficacy scale (RESES) and self-rating depression scale (SDS). The statistical analysis was performed using SPSS 19.0 software. Results Total score of psychological quality and scores of 3 dimensions, including cognition, adaptability and personality, were significantly positively correlated with the score of expressing positive emotional self-efficacy (r=0.74, 0.57, 0.41, and 0.67; all P<0.01) and managing negative emotional self-efficacy (r=0.78, 0.65, 0.37, and 0.64; all P<0.01). The scores of psychological quality and regulatory emotional self-efficacy were significantly negatively correlated with depression (psychological quality and 3 dimensions:r=-0.78, -0.54, -0.50, and -0.62, all P<0.01; expressing positive emotional self-efficacy:r=-0.60, P<0.01; and managing negative emotional self-efficacy:r=-0.65, P<0.01). The military medical college graduate students having high regulatory emotional self-efficacy level had significantly higher score of psychological quality and significantly lower score of depression compared with the students having low regulatory emotional self-efficacy level (t=14.71, -9.43; both P<0.01). Expressing positive emotional selfefficacy had partial mediating effect between 3 dimensions of psychological quality and depression, and the proportions of total effect were 22.38%, 6.25% and 24.75%. Managing negative emotional self-efficacy had partial mediating effect between 3 dimensions of psychological quality and depression, and the proportions of total effect were 24.80%, 13.50% and 24.54%. Conclusion Regulatory emotional self-efficacy has partial mediating effect between psychological quality and depression in military medical college graduate students.