The invention relates to an auxiliary control system for economical operation of a regional electric network transformer, which is applied to the technical field of electric power. The system comprises a database module, a communication module, an analysis and calculation module, a graphic display module, a report management module and a system management module, wherein the input end of the communication module is respectively connected with an automatic dispatch system and the analysis and calculation module to receive the measured data and form an economical operation control policy and an optimized operation curve to be output to the system management module, the graphic display module and the report management module; the database module is connected with the communication module to transmit the measured data; and the output end of the database module is connected with the analysis and calculation module to transmit the measured data, the economical operation control policy and the optimized operation curve. The invention can realize the purpose of controlling the overall process to be completed automatically, can greatly reduce the working strength of field operators, reduce the network loss and increase the power factor at the load side of the electric network, and has positive significance of energy saving and consumption reduction for the whole electric power system.