Abstract: Discusses the multi perspective and hierarchical character in dividing a product into different modules by developing an approach to divide the product into hierarchical modules. According to this approach, the product is firstly, divided into a set of functional units the dependency matrix between the function units are then defined. The function units are then integrated into modules according to the intentions of different users and designers. The validity of the method is proven using a case study on the division of a lathe into its hierarchical modules.