Web service is the kernel and key of the solutions of the new generation dynamic E-commerce and enterprise application integration (EAI), so the dynamic E-commerce is the goal of E-commerce development. SOA and web service can ensure a compatible information exchange and integration framework for the business process of the dynamic E-commerce, and it has led to a more complex type of web interaction and collaborations between enterprise trading partners, This paper discusses service-oriented architecture, web service and relating protocol standard. Finally, a dynamic E-commerce application architecture based on SOA and web Service is presented.