Given the demands of high efficiency maintenance of charging piles in large-scale electric vehicle application, this paper, based on the basic principle of the blockchain, analyses the high distributive, multi-agent, and highly reliable features of the charging piles maintenance system first. Then it continues with the application value of a blockchain in a charging piles maintenance system. Thirdly, a blockchain-based charging piles maintenance system is proposed by using alliance chain style, adopting a PBFT consensus mechanism, and including complete & incomplete nodes. Finally, according to specific application scenarios, the functions of the proposed blockchain-based charging piles maintenance system are analyzed from the aspects of service, management and data structure levels. The proposed blockchain-based charging piles maintenance system is able to provide an end-to-end transparent and high reliability management mode for multi-agents including the charging pile, power distribution station, maintenance, calibration and supervision institutions. This provides an example of the implementation of blockchain technology in a charging pile maintenance system. This work is supported by Science and Technology Project of the Headquarter of State Grid Corporation of China (No. 52110418001P).