Abstract: A structure of Web-based virtual design system is presented in the paper. The approach in the design system on real time interactive processing to the VRML model of the product is presented to exhibit the product on the Web page, which includes the method of defining the interactive nodes in VRML model, the logic relation between the predefined interactive nodes and the database, and the algorithm used to process the real-time VRML model based on the predefined information. The algorithm has been implemented in the prototype of a Web-based virtual design system.