The invention relates to a power supply method of a light weapon firepower control system using a super capacitor, comprising a battery opening power supply which is used for supplying power for the light weapon firepower control system; a variable current controller arranged inside a power supply circuit can be switched into a low-current control model according to the detection result of a microprocessor; the super capacitor is pre-charged by a battery through a voltage stabilizing diode arranged inside the power supply circuit; the microprocessor leads a boost converter to be switched into a first boost state with lower boost quantity, and the variable current controller to be switched into a high-current control mode at the same time; the super capacitor is continuously charged by the battery through the voltage stabilizing diode and the boost converter in the first boost state; the microprocessor leads the boost converter to be switched into a second boost state with higher boost quantity; the super capacitor is continuously charged by the battery until being fully charged; the microprocessor leads the variable current controller to be switched into an intermediate-current control mode; and then, the battery and the super capacitor discharge in a united way, so that instantaneous high power can be released.