Military service system transformation has caused heavy workloads and work–family conflict among professional military personnel, resulting in the vicious circle of increased turnover intention and shortage of manpower. Recent studies have demonstrated that positive traits such as grit may help to address issues facing military personnel. To construct the model and explore the moderation effect of grit, 884 military personnel completed self-report questionnaires on work-family conflict, grit, burnout, depressive tendency, and turnover intention. Structural equation modeling and regression analysis using PROCESS macro were used to test the model. While gender is not a significant contributor to work–family conflict, marriage, age, and ranks are. Work–family conflict is negatively correlated with burnout but positively associated with depressive tendency and turnover intention. Grit mitigated the effect of work–family conflict on depressive tendency, but not that on turnover intention. Practical implications for military guidance, education, and future research are discussed.