In the 21st century, with the further deepening of informationalization, competition among the steel industry chain has gradually upgraded to that of its e-commerce service. On the basis of bus-based industry chain theory, the architecture of integrated e-commerce platform in the steel industry chain is built. The platform involves upstream and downstream enterprises, including manufacturers, processing centers, trading companies, third-party logistics companies, and customers, etc. different from previous decentralized model of e-commerce platform, through the integrated e-commerce platform, customers can complete all business with one-stop, and improved their service perception and satisfaction. And new model is more promoted and implicated in other industry. The system has been applied in the enterprises, and the result is very good. The bus-based integrated e-commerce platform will become one of the paths for enterprise to further development.