The invention provides a transformer cooling control system, which comprises a controller. The transformer cooling control system is characterized in that the controller is connected with a temperature sensor and a load sensor through an analogue expansion module; the controller is connected with an upper computer through a network transmission module; the controller is connected with an expansion board through a digital expansion module; and the expansion board is connected with a group of blower fans. The cooling automatic control system takes the PLC S7-200 from Siemens as the controller, is provided with the analogue expansion module for obtaining signals transmitted by the temperature sensor and the load sensor, is provided with the network transmission module EM277 for connecting a PROFIBUS network to realize data exchange with the upper computer, is provided with the 8-input and 8-output digital expansion module for connecting with the determinant I/O expansion board, and obtains feedback signals of the 32 blower fans through six input ports and six output ports.