The substation has the features of a large quantity and wide-area distribution. With the promotion of unattended mode, it has become increasingly difficult to adapt to the needs of smart grid development using traditional field-based automatic equipment operation and maintenance(O&M) method. Meanwhile, there is a shortage of professional and technical personnel, and the O&M technology of a large number of intelligent heterogeneous secondary equipment is complicated and challenging to maintain. Therefore, it is urgent to solve the problems of O&M efficiency, timeliness and technical complexity of a large number of substations. Based on the service-oriented idea, this article has designed the overall structure of the trinity of service management center, O&M center and O&M substation. This paper also proposes a GSP-based service standardization interaction mechanism. Through Safety management and control process of O&M service, O&M advanced applications are designed to achieves the automation equipment specification, safe and reliable remote operation and maintenance.