Objectives The aim of this study was to identify risk and protective factors of suicidality among Korean military officers. Methods This study was conducted on 3162 military officers. Data were collected by online survey after obtaining informed consent. Demographic characteristics, depression, anxiety, suicidality, social support, stress, and attitude toward suicide were evaluated using structured instruments and self-report questionnaires. Suicidality was defined as having a suicidal idea, a suicide plan, or attempting suicide. Statistical analysis was performed using logistic regression to investigate associations between potential risk and protective factors and suicidality. Results Depression (odds ratio [OR]=16.313, 95% confidence interval [CI]=10.028-26.539), anxiety (OR=14.377, 95% CI=8.680-23.812), and stress (OR=8.116, 95% CI=4.637-14.207) were positively associated with suicidality. On the other hand, good social networks and an unaccepting attitude toward suicide were negatively associated with suicidality (OR=0.131, 95% CI=0.072-0.240). No significant correlation was observed between living status and suicidality (OR=0.991, 95% CI=0.598-1.642). Conclusion Depression, anxiety, and stress were found to be risk factors of suicidality among Korean military officers. In contrast, good social networks and unaccepting attitudes toward suicide acted as protective factors. Hence, preventive interventions that place focus on risk and protective factors should be developed and implemented to mitigate suicidality.