The invention discloses a method and a system for filtering narrow pulses from PWM driving signals of a cascaded converter, belongs to the technical field of cascaded converters, and solves the problem of narrow pulses existing in a conventional cascaded converter. The method for filtering narrow pulses from PWM driving signals of the cascaded converter comprises the following steps of: performingreal-time sampling of a PWM signal into an IGBT driver to obtain the logic level value v1 of the PWM signal, sampling the PWM signal input into the IGBT driver again to obtain the local level value v2 of the PWM signal; if v1 is not equal to v2, ending the current round of sampling, and taking the logic level value of the PWM signal output by the previous round of sampling as the output of the current round of sampling; otherwise, continuously sampling the PWM signal input into the IGBT driver in real time, and finally determining the output of the current round of sampling according to the logic level value obtained by two adjacent times of sampling or the set value of the sampling times of the current round. According to the method, the interference narrow pulse of the PWM driving signal of a cascaded converter can be filtered, and the narrow pulse existing in the original PWM signal can also be filtered.