This paper proposes a new Distributed Real-Time Database (RTDB) architecture for a dispatch automation system with micro-services, which solves the problems of slow data processing, poor flexibility and difficult expansion in the RTDB of the traditional dispatching automation system. According to the requirement of RTDB for data timeliness, the simplified data model of telemetering class and remote signal class is defined, which avoids the search of complex data relation. Meanwhile, the data fragmentation technology is used to divide the data effectively. Utilizing micro-services architecture pattern, the data read and write process is virtualized into fine-grained data services, and the core of cloud computing technology is used to realize the deep integration of micro service and distributed technology. On this basis, the distributed real-time database management system has been applied in an actual power grid. The actual operation results show that the RTDB under this method has the advantages of high real-time, strong scalability, stable and reliable operation, and provides technical support for the construction and development of strong smart grid. This work is supported by National Key Basic Research Program of China (973 Program) (No. 2013CB228205) and National Natural Science Foundation of China (No. 51167003).