The biggest difficulty in the process of finite element (FE) analysis is the modeling of industorial products that have complex configulation. To overcome this, prototype of integrated finite element modeler, MODIFY (MODeling tool for Integrated Finite element analYsis) is developed by the authors [1]. MODIFY has three features : (1) FE modeling by the part object concept, (2) fully object-oriented data structure, (3) fully automated part by part mesh subdivision. In MODIFY, part objects consist of the geometry objects, the analytical condition objects and the relation objects, and the user only need to define and assemble them. The prototype system is applicable to FE modeling for 3-D plate structures. In this paper, MODIFY is extended for 3-D shell structures. Three enhncement was made. First, the shell object that is represented by B-rep model and rational B-spline surface is defined as a geometry object. Second, the mesh generator for 3-D curved surface is constructed. Finally, MODIFY is linked with external CAD syntem using IGES file, which is most widely used as a conversion in commercial CAD system. Several examples of finite element model generated by MODIFY are shown.