Abstract: In order to make better use of the large underground space resources left behind by abandoned coal mine, this paper preliminary constructs and designs a type of pumped storage peak shaving system. Based on the coal mine underground reservoir technology, the system makes the coal mine goaf to store and purify the coal mine water.By utilizing the discrepancy in elevation between the earth surface and underground, and the discrepancy in elevation among the different mining level coal mine goafs, the system stores electric energy by pumping water during low power grid load, and supplements power grid by draining water for power generation during high power grid load.Besides, this system also designs a coal mine water treatment unit by using electrochemical technology and purifies mine water for production and daily life by using excess power.This paper discusses the system work principle and system basic structure, and verifies the feasibility of the system by case-based design. This pumped storage plant overcomes the location limitation of traditional pumped storage power station, greatly reduces the construction cost and period，and makes up short board for the lack of peak load regulation in China’s power grid. It provides a new development direction for abandoned coal mine and the utilization of underground space resources in China.