Purpose : The purpose of this study was to investigate the effect of the aquatic exercise program on lower muscle strength, balance and gait activity on 12 weeks aquatic exercise program in the elderly women. Methods : The Subjects in this study were 20 aged 70s who were long-term residents admitted to elderly nursing home of S, Gyeongsangnam province. They performed aquatic exercise programs 60-minute sessions, 3 times a week for 12 weeks. The physical evaluation was used for measuring lower muscle strength, balance activity was used for measuring balance testing, and gait activity was used for measuring gait velocity and maximal step length evaluation. All data were analyzed by paired t-Test by SPSS(version18.0). P-values of <.05 were considered significant. Results : Lower extremity muscle strength, static dynamic balance and gait activity were significantly increased both in the exercise group and between groups. Conclusion : This study suggests that aquatic exercise program has an effect on lower extremity muscle strength, balance and gait activity of the elderly women. Therefore, it is considered as a safe and helpful self-support activity for the elderly people.