Background: Mental disorders are one of most common reason for early separation of soldiers from the military service. The purpose of this study was to evaluate the relation of self-mutilation and personality disorder among soldiers. Materials and methods: In this case-control study, 30 soldiers referred to an army psychiatric hospital (cases) and 30 soldiers referred to another military health center (controls) were evaluated for personality disorders by clinical interviews on the basis of DSM-IV criteria. The frequency of self-mutilation and personality disorders were then analyzed by SPSS statistical software. Results: Totally, 63.3% of case group and 6.7% of control group had history of self-mutilation. The frequency of personality disorders was 56.7% and 20% in cases and controls, respectively. In case group, 78.9% and 18.2% of patients, respectively, with and without a history of self-mutilation, had cluster B personality disorder (P=0.002). This difference remain significant among control group (P=0.003). Conclusion: Regarding the relationship between self-mutilation with cluster B personality and impulsivity of these personalities, detection and preventive treatment of patients or exempt in severe cases prior to entering military service may be useful for reducing the incidence of self-mutilation and suicide.