The invention discloses a method and a device for improving the performance of an intrinsic safety switching power supply in an explosive dangerous environment. By adoption of the method for detecting the change rate of a current by an inductor, a main circuit is cut off; the time of the current change during short circuit is delayed by the inductor to make the current start rising after a voltage is reduced to zero, so discharging energy during the occurrence of a fault is reduced; and the change rate of the current during the short circuit is controlled by the inductor, so the influence of electromagnetic interference (EMI) is reduced. A current differential measurer of the device is connected with an input end of a driving circuit; an output end of the driving circuit is connected with control ends of switches; the first switch is connected in series with a current-limiting inductor; the second switch is grounded by a load resistor (RL); the current-limiting inductor is connected in parallel with a diode; and the current-limiting inductor and the diode which are connected in parallel are grounded by the RL. The invention has the advantages that: the power of the intrinsic safety switching power supply is improved; the safety and reliability of an intrinsic safety system are improved; the change rate of the current is reduced; and the EMI is reduced.