Abstract: The intelligentization of urban rail transit substation will reform the conventional operation and maintenance mode that is used to be passive, planned and man-made, so as to realize intelligent operation and maintenance, thus improving the efficiency and reliability of power supply system. The intelligentization of primary equipment is the essential foundation for realizing the overall intelligence of substation. Through analysis of intelligent substation system architecture and technical characteristics, the intelligentization of main primary equipment in substation is analyzed and the functional requirements and structural framework are proposed considering the characteristics of urban rail transit power supply system. The system architecture of urban rail transit intelligent substation is preliminarily constructed, providing reference for the following in-depth study of urban rail transit substation intelligentization.