The utility model discloses a parallel gap lightning protection device, which comprises an insulator, and an upper metal electrode and a lower metal electrode respectively connected with the upper end of the insulator and the lower end of the insulator, wherein the lower metal electrode is connected onto the lower end of the insulator via an adjusting mechanism; the adjusting mechanism comprises a fixing piece connected onto the lower end of the insulator, a moving piece adjusted vertically in relative to the fixing piece and a locking assembly connected between the fixing piece and the moving piece; with the locking assembly, the moving piece and the fixing piece can be locked and the lightning protection gap distance can be fixed; and each of the upper metal electrode and the lower metal electrode comprises a connection rod and a tungsten copper alloy ball fastened at the end part of the connection rod. The tungsten copper alloy ball has good ablation resistance and good welding resistance and can replace carbon steel to serve as better electrode material, the detachable structure facilitates replacement of spare parts, and the operation is more convenient and quicker.