The invention provides a response characteristic testing device for metal oxide samples under steep pulse. The response characteristic testing device comprises a steep wave front pulse current pulse generating device and a tester, wherein the steep wave front pulse current pulse generating device is used for generating steep wave front current waveforms, and the tester is used for testing current and voltage waveforms of samples. Samples are connected in a loop formed by the steep front wave pulse generating device, three electrode switches are punctured by charging two capacitors of the steep wave front current pulse generating device by a direct-current power source, so that response characteristics of the metal oxide samples under the steep wave front pulses are tested. The response characteristic testing device of the capacitor and switch integrated structure reduces inductance of the loop, and by wrapping the capacitors compactly by copper strips, inductance of the loop is reduced to the greatest extent, sufficient current amplitude value and steep rising edges are guaranteed, and valve disc residual voltage under the steep waves is evidently improved along with increase of the steep wave front current.