The invention discloses a mini LED television control system and method. The system comprises a power supply which is used for adjusting a voltage and then supplying power to backlight boards; a control board which is connected with the power supply, wherein the control board comprises an FPGA which is used for detecting a current value and controlling a power supply output voltage, an analog-to-digital conversion chip which is used for collecting the voltages of sampling circuits, and a plurality of sampling circuits which are connected with a plurality of light boards and are used for collecting light board voltages; constant current ICs which are set on the light boards and are used for providing light bar voltages and sending brightness information; and a mainboard which is connected with the control board and is used for enabling and synchronizing backlight brightness signals. The control board is used for converting the brightness information sent by the mainboard and then sending the information to the constant current ICs on the corresponding light boards. The constant current ICs control currents of corresponding subarea LED lamps. According to the system and the method, through utilization of a power supply voltage, an output closed loop control system can be adjusted, so the power supply outputs the most suitable voltage, and integrated losses of a mini LED television are reduced.