Recently, low back pain of laborer is social issue in Japan. This problem is caused by excessive load on waist joint or uncomfortable posture of heavy labor, such as lifting up heavy objects. To resolve the problem, we have developed endoskeleton-type power assist suit. In previous study, the design and operation method of the assist suit was designed using simple static model. However, this method is insufficient for designing the assist suit because structure of human body is more complex than the model practically. Therefore, we use the musculoskeletal model to design the assist suit and its operation method in this paper. Firstly, motion of worker is analyzed using 3D motion capturing and this results are applied to musculoskeletal model “Anybody”. Secondly, with these simulation results, the assist suit and its operation method are designed. Finally, effectiveness of the assist suits confirmed by measurement of electromyography and assistive force.
