The popularization and application of the smart power dispatching control systems propose new requirements to the system operation and maintenance work. Therefore it is in urgent need of changing the current decentralized operation mode, and establishes centralized operation and maintenance standardized work processes to achieve the whole system operation and maintenance intensification, automation and mutual assistance. The present situation of the operation and maintenance and the necessity of centralized operation and maintenance are analyzed. The function framework, safety precaution, standardized process and technical implementation plan of whole system centralized operation and maintenance are put forward, and the key technologies are discussed. The centralized operation and maintenance center of smart power dispatching system has been completed and put into operation, which show that the centralized mode can effectively improve the system stability and security. This work is supported by Science and Technology Project of State Grid Corporation of China:Research on Technical System for Global Energy Interconnection (No. SGTYHT/15-JS-191).