Purpose: The purpose of this study was to investigate the effect of exercise on mental health in female elementary school teachers. Methods: The subjects were 1,861 female elementary school teachers in Seoul. Data were collected through an online survey from November 16 to December 7, 2008. Collected data were analyzed by descriptive statistics, ${chi}^2$-test, t-test, one way ANOVA and Scheff$acute{e}$ test, using IBM SPSS 20.0 program. Results: Not many female elementary school teachers were engaging in exercise. Even though their perception of stress and degree of depression were high, the rate of suicidal thoughts were low. The perception of stress was lower in the female teachers who engaged in walking or high-intensity workout than those who did not. The teachers who walked or stretched for exercise showed a lower rate of depression than those who did not and the teachers who walked for exercise displayed a lower rate of suicidal thoughts. Conclusion: Exercise programs should be provided for female elementary school teachers to reduce their stress, depression, and suicidal thoughts.