Progressive step-by-step discharge device

The invention discloses a progressive step-by-step discharge device. When the progressive step-by-step discharge device is matched with a lightning protection insulator or a lightning protection insulator strain clamp (string) with a discharge gap, a power frequency arc triggered by thunder and lightning can be quickly extinguished in a lightning stroke, a line is prevented from being damaged by the lightning stroke and the lightning trip-out frequency is eliminated or reduced. The progressive step-by-step discharge device comprises a discharge cabin made of a solid insulating material, two metal main electrodes and N (N is greater than or equal to 2) metal transition electrodes, wherein the transition electrodes are arranged in the discharge cabin along the inner wall. The space between any two adjacent electrodes (including the main electrodes and the transition electrodes) is never greater than the linear distances between any electrode in the two electrodes and any other electrodesexcept for the adjacent