The paper introduces the current status and the problems of servers in the data center of Institute of Medical Information, Chinese Academy of Medical Sciences, points out the necessity of virtualization in data center, expounds the concept of virtualization and server virtualization technology, then describes the implementation scheme of constructing the server virtualization platform based on VMware vSphere 5.5 products in detail. Finally, the application effect of server virtualization is summarized and the future work is prospected.