The large-scale integration of distributed generation poses challenges to the reliable operation of distribution networks. Proper regulation of multiple user side flexible resources can inject new vitality into the flexible operation of distribution networks. However, traditional centralized control methods in distribution networks are difficult to cope with the energy management and information interaction needs of numerous nodes. This paper proposes an optimal operation method for distribution substation areas focusing on the power aggregation of multiple flexible resources. First, based on Monte Carlo algorithm, this paper aggregates power from flexible controllable resources, such as electric vehicle charging load, air conditioning electric load, interruptible load, and user side energy storage in a multidimensional manner within the substation area. On this basis, models of electric vehicle charging load, air conditioning electric load and interruptible load participating in different types of demand response are established, and a multi-objective coordinated optimization method is proposed that considers both economic efficiency and energy comfort in the operation of the distribution substation area. Finally, an analysis is conducted on a county-level distribution substation area, and the demand response potential of multiple flexible resources is evaluated. The results verify the validity of the established model and proves that the proposed optimal operation method can effectively increase the photovoltaic consumption rate of the distribution network.