On the basis of the common information model and the OPC unified architecture, this paper studies the construction of distribution and utilization grid data platform to support comprehensive data analysis, including system architecture and information model research, data management, service system construction, and data aggregation. A unified information model is formed through analyzing the data in each distribution and utilization business system, tailoring the IEC TC57 common information model accordingly, and supplementing undefined elements in the CIM. The mapping rules of information model and object data to the OPC unified architecture information model are established. After the data of distribution grid and utilization system from multiple business systems have been standardized and aggregated according to the unified information model, all schema and object data are managed in the OPC unified architecture address space. Services defined by the OPC unified architecture are implemented to provide secure and efficient data access support for analysis applications. The data platform is organically coordinated with the business systems and comprehensive analysis applications, and its technical scheme has been put into practice in engineering. This work is supported by Science and Technology Project of China Southern Power Grid Ltd (No. GDDWKJXM 00000025).