Objective To investigate the mediation effects of coping style on the relationship between mental resilience and negative emotions among military personnel. Methods A questionnaire survey was performed in 358 military officers and soldiers using Connor-Davidson resilience scale, simplified coping style questionnaire and depression anxiety and stress scale. Structural equation model was built to analyze the relationship between variables. Results A total of 344 valid questionnaires were collected, and effective response rate was 96.09%. All the subjects were male with a mean age of (23.24±4.73) years old. Pairwise correlations between mental resilience, positive coping style, negative coping style and negative emotions were all significant (all P<0.01). Mental resilience explained 21.2% of the total variation of negative emotions (P<0.01), and coping style explained 7% of the variation. Mental resilience could indirectly affect negative emotions through positive coping style and negative coping style (χ²=35.744, df=17, χ²/df=2.103, goodness of fit index[GFI]=0.975, adjusted goodness of fit index[AGFI]=0.948, root mean square error of approximation[RMSEA]=0.057). The mediation effect of coping style accounted for 27.03% of the overall effect (positive coping style for 75.43% and negative coping style for 24.00%). Conclusion Coping style plays multiple mediating roles between mental resilience and negative emotions in military personnel, especially with the positive coping style contributing a large proportion. Therefore, it is necessary to focus on training positive coping style in military personnel with low mental resilience, so as to effectively reduce the level of negative emotions of military personnel and improve operational efficiency.