A method for testing a power module includes connecting an output capacitor of the power module to a load meter; inputting an input signal, an enable signal, a PowerGood signal, and an output signal of the power module to first, second, third, and fourth channels of an oscillometer, respectively; adjusting the load meter to a no-load state, and capturing and storing the power-on waveforms and power-off waveforms of four channels of signals of the power module; adjusting the load meter to a full-load state, and capturing and storing the power-on waveforms and power-off waveforms of the four channels of signals of the power module; and determining whether the power-on sequence, power-off sequence, overshoot voltage value, and undershoot voltage value of the power module are normal based on the power-on waveforms and power-off waveforms of the four channels of signals stored by the load meter under the no-load and full-load states.