ERP is an important way and tool for enterprises to implement informatization construction, and it is an important foundation and strong support for enterprises to carry out e-commerce business. The purpose of this paper is to design an ERP platform for small and medium enterprises based on Azure Windows cloud computing. On the basis of in-depth understanding of the basic concepts and principles of cloud computing, e-commerce and ERP systems, the ERP platform of e-commerce cloud e-commerce system is designed and completed. Use cloud computing to reduce the cost of writing business information, reduce business risks, and provide personalized business services. And using the proposed reliability model in a cloud computing environment, the reliability value is 0.66, while exposure to high unprotected power sources triggers a reliability review. In the multi-tenant architecture area, the data between the application area and the tenants is separated to ensure that different tenants and different modules in the same tenant do not affect each other, and the security of the application system is ensured.