In order to implement a product model which can be applied to shipbuilding industry, the authors have developed the integrated system called SODAS (System of Design and Assembling for Shipbuilding). In the design stage, SODAS is able to generate product information such as “Room” and “Part”. In the system, it is mainly considered how the product information is generated. In this paper, the system is revised up to a level of conceptional use. Particularly, deep consideration is paid for relation of product information which is not proposed in SODAS. In order to realize this, some new concepts are introduced. What and how relation informations should be described in the system is mainly discussed. Some examples are shown. One is an application to design modification which is not applied to the existing SODAS. Another is the use of design procedure information for a new ship, by using design procedure information which were already done in past.