In ship design, the hull design is completely different from the outfitting design. The CAD systems for the hull design and for the outfitting design are also different although they model the same ship. This difference raises many problems including interference check. During this thesis work, the method of checking interference between hull elements and outfitting elements based on the GWB solid modeler, and the generation of the STEP AP203 physical file have been implemented. The STEP file can play the role of migration path between the legacy CAD systems and a new generation CAD system. The STEP data stored into a RDB can be shared by many users, even on the internet using the methods of CGI, Java, CORBA.