The inner space of building is increasingly becoming complex as urban activities increase in variety, and the actual space size also increases. This trend necessitate the utilization of three dimensional position information within the inner space of buildings. Standard GIS web service technology and visualization technology are applied to 3D inner space building data to share these information for better decision making in building related applications such as fire evacuation, facilities management and market analysis. This study aims to effectively model and visualize the three dimensional space of building interiors in the GIS aspect, and to be able to share the information through standard GIS web service. The various elements of inner model was assigned and stored into pre-designed spatial database tables respectively. GIS web server was then configured to service the database which was populated with 3D inner model data. On the client side, 3D visualization modules was developed using a 3D graphic rendering S/W engine.