Based on the analysis of the shortcomings of current online virtual stores, the concept of the three-dimensional ecommerce model is proposed by combining with the new demands of e-commerce and features of Web3D technology in this paper which emphasizes the inevitability of the usage of Web3D technologies in e-commerce, On this basis, the paper describes a designing strategy of virtual online shopping mall which is based on the Web3D technology through analyzing the implementation of Web3D. The main functions and features of the system are discussed in detail, the basic design ideas of the system was also illustrated. A three-dimensional virtual shopping environment is provided for the user.