After the large-scale renewable energy is connected to the grid, the traditional reserve system has the problem of poor economy and reliability when dealing with the bilateral randomness of the power supply side and the load side of the power system. To ensure the safe and stable operation of the system, it is necessary to study the configuration and optimization methods of the system reserve. This paper expounds the impact of large-scale renewable energy grid-connected on power system reserve, fully explores various types of reserve resources of the system and expounds the three types of reserve resources of source, load and storage and their research status as cross-regional reserve of interconnected power grids, in order to deal with various long-term, large disturbance, large-capacity power shortage risk events faced by the system under large-scale renewable energy grid-connected environment. This paper analyzes in detail the various methods for configuring the reserve capacity of power systems, reserve dispatching optimization, and points out the research direction of the next stage, which provides reference for the research on the reserve configuration and optimization method of the power system in the context of large-scale renewable energy grid connection.