Meteorological data play a fundamental role in processes of meteorological operations and services. In recent 20 years, China has rapidly developed traditional and newly observational systems, which produce a large volume of meteorological data and products. To meet requirements of data management and services, China Integrated Meteorological Information Sharing System (CIMISS) is developed by National Meteorological Information Center of China Meteorological Administration. The design principle, system structure and data flow, and core technologies of this system are introduced and illustrated in detail. CIMISS is composed of five sub-systems, which are China Telecommunication System (CTS), Data Processing Center (DPC), Service-Oriented Database (SOD), Global Data Sharing (GDS), Monitoring and Control Platform (MCP). CIMISS is designed for undertaking a series of operations of meteorological data collecting, processing, storage, retrieval and dissemination. Data cover all real-time and historical meteorological observations and products, including 14 classes that are surface, upper-air, solar radiation, oceanic meteorology, agro-meteorology, radar, satellite, proxy climate, atmospheric chemistry, numeric model analysis and forecast, scientific experiment, meteorological disaster, meteorological service product and the others. Data cover the geographic area from China to global, and the period from 1951 to now. Real-time data come from all kind of meteorological observation networks in China, and the Global Telecommunication System of World Meteorological Organization.A set of information technologies are introduced and developed to design and implement the system, including inner-system message switching based on message middleware and the parallel file system, classification and representation of meteorological data, the dynamic extension of data processing scheduling and algorithms, the design and application of 3 types of metadata, the management of common configuration information, monitoring and controlling for whole procedures of operational flow, service-oriented data storage strategy, the unified accessing view and application programming interface.CIMISS will manage all kinds of operational meteorological data used in national and provincial meteorological operations and services, and supply data application environment for operations of national service centers and 31 provincial service centers. Users can access the data by Web page and by application programming interface (API).