One of the features of Japanese product development is product integrity development that can obtain a multi-objective satisfactory design solution by close collaboration among different designers and teams. This product development depends on the contributions in personnel by trial and error, therefore these designers bear a heavy burden. This paper proposes a design support method for product integrity development by using a set-based design method and agent technology. The proposed method obtains intersection of sets that satisfies multi-objective performances within compromise design set of each team by the set-based design method and then shows design suggestions to a designer for obtaining a design solution from the intersection of sets based on the result of analysis and design knowledge by agentifying 3D-CAD solid models with attribute information, design knowledge and design evaluation. This paper also develops a design support system based on a proposed method and discusses its possibility for product integrity development.