Objectives : To evaluate the effects of a strengthening exercise program on the physical activity, activities of daily living(ADL), social behavior and functional performance of the elderly in a home for the aged. Methods : We administered a survey questionnaire that consisted of questions to establish general characteristics, health habits and status, physical activity, ADL, and social behavior. Additionally, a physical fitness and functional performance examination was peformed on subjects who were 65 years old or older. Study subjects numbered 33 in the experimental group and 35 in the control group. For intervention, we used a strengthening exercise program of the upper and lower limbs for 12 weeks(5 times/week) using dumbbells and lead-packed weights. Results : After the strengthening exercise program, the scores of physical activity and social behavior were significantly higher than the control group and the before exercise measurements. Moreover, the variables of functional performance were significantly higher than in the control group or the before exercise records. Conclusion : These results Indicate that a strengthening exercise program can improve the score of physical activity, ADL and social behavior, as well as decrease the time(sec) of functional performance of the elderly in a home for the aged.