Recently, not only marine PLM (Product Lifecycle Management) system but also an effective outfitting BOM (Bill of Material) management has been attracted by many shipyards. In particular, efficient outfitting design is being one of major issues in shipyards since most of currently designed marine vessels have more complex outfitting system than ever. Furthermore, each outfitting system has huge number of parts that should be arranged based upon the procurement and installation plan. Outfitting BOMs evolve into different forms according to the product development phases during basic design; detail design; and production design. Therefore, it is very difficult to maintain a consistent BOM data during the design phases. In order to express the evolution of product structures and the information of outfitting along the ship design, we suggested UID (Unique ID) code system. The UID (Unique ID) is used in order to create the relationship within evolutional BOMs of each design stage. It utilizes as the procedure of weight calculation for procurement BOM during each design stage. Thereafter, in order to demonstrate suggested outfitting BOM management technique, we suggested a prototype. In the prototype system, suggested features of outfitting BOM are implemented.