Minimizing environmental loads and costs throughout a product lifecycle requires appropriate lifecycle design as well as the design of the product itself. Design of a product involves planning lifecycle strategies, evaluating it from various viewpoints and optimizing the overall picture based on the product and market properties. Product lifecycle strategy can be planned by describing lifecycle scenarios at an early stage and the product architecture should be designed so as to realize the scenario. In this paper, we propose a design support method for product structure design based on lifecycle scenarios. Our method links a lifecycle flow, as a central model of a lifecycle scenario, to product structure by unifying components that go through the same path in the lifecycle flow. The designed structure, therefore, leads to easy management of components throughout the lifecycle and reduce the environmental loads and the costs of lifecycle processes.