(On the basis of discussing the concept and characteristics of SaaS, this paper summarizes and analyzes the use of enterprise information service mode based on SaaS, including the use of customer relationship management (CRM), enterprise resource plan (ERP), e-commerce (Ec), supply chain management ($CM), office automation (OA) and other aspects. Then it summarizes the problems in the construction of enterprise information service based on S beat S, including the scope of application, security, operational efficiency and risk.)