The invention discloses an impedance scanning method for power electronic equipment. The method includes the following steps: obtaining a plurality of scanning frequencies; constructing a system undertest including the power electronic equipment, and injecting a harmonic voltage under at least one scanning frequency into the system under test; when the system under test is in a stable operating state, outputting the port voltage and the port current in an operating result under each harmonic voltage, and storing the port voltage and the port current as corresponding data files; reading each data file to obtain a harmonic voltage amplitude, a harmonic voltage phase, a harmonic current amplitude and a harmonic current phase at each scanning frequency; and calculating the impedance magnitudeand the impedance phase according to the harmonic voltage amplitude, the harmonic voltage phase, the harmonic current amplitude and the harmonic current phase. The embodiment of the invention also provides an impedance scanning system for the power electronic equipment. The embodiment of the invention can be applied to the power electronic equipment, fully reflects the influence of the control system, is accurate in test result, and greatly reduces the workload of impedance scanning.