During manual work in shipbuilding such as blasting, grinding, and so on, a large force is acted on the body of a worker. As a result, this work induces musculoskeletal disorders of the worker and it also induces severe social problems. To solve this problem, we are developing a work support robot for the prevention of musculoskeletal disorders in shipbuilding. In this study, a result of conceptual design of this robot is presented. A worker can perform the blasting work with a small force using this robot which can lessen the force acting on the body of the worker.