Piping work is consist of design, making and installation. Pipe line is consist of spool pipes which are made in fabrication shop. And these spool pipes installation in shipyard. Design of spool pipe is not based 3D CAD model, using 2D Drawing(ISO Drawing). Therefore, not consider working area, that wake decreasing working efficiency and delay working time. In this paper, suggest make spool pipe design method using analysis working area about 3D CAD model and genetic algorithm.