Objectives : The purpose of this study is to investigate the effect and adverse events of Gamiwolbigachul-tang on the changes of body composition and musculoskeletal pain in overweight patients. Methods : A total of 28 patients with overweight patients who were complaining musculoskeletal pain were treated with Gamiwolbigachul-tang more than 4 weeks between January 2011 and August 2011 in Kyung Hee University Oriental Medical Hospital were observed. We have evaluated the efficacy of treatments by measuring the changes of body composition (Body weight, Body mass index, Skeletal muscle mass, Body fat mass and Waist hip ratio) and musculoskeletal pain. The 28 patients were analyzed according to the distribution of sex, age, body compostition and musculoskeletal pain. Results : 1. There were statistically significant changes on Body weight and BMI in 28 patients after 4 weeks of treatment. 2. Gamiwolbigachul-tang had effect on reducing Body fat mass rather than Fat free mass. 3. There were statistically significant changes on musculoskeletal pains such as lower back pain, knee pain after treatment. 4. There were few side effects except those common complications such as insomnia(3 patients), palpitation(2 patients) and indigestion(1 patients), which did not have effects on everyday living. Conclusions : These results suggest that Gamiwolbigachul-tang will be beneficial for overweight patients with musculoskeletal pain, having both effectiveness and safety.