The his system based on B/S architecture, if no server is needed, is deployed in the cloud and delivered to micro-medical institutions in the form of software as a service (SaaS), which eliminates the problems of medical institution customers in it infrastructure construction, software and hardware deployment, post-operation and maintenance, and allows medical institutions to subscribe on demand and realize on-demand payment operation. This is suitable for small and medium-sized medical institutions, such as Yunxing Yunhis system.