The invention provides a parallel gap device for an anti-thunder insulator. The parallel gap device for the anti-thunder insulator comprises a double-ring electrode, an upper discharge electrode 4 anda lower discharge electrode 8, wherein the double-ring electrode is connected with the insulator in an insulating way, the double-ring electrode is arranged between discharge gaps of the upper discharge electrode 4 and the lower discharge electrode 8, and the distance between the double-ring electrode and the lower discharge electrode 8 is less than the distance between the double-ring electrodeand the upper discharge electrode 4. The double-ring electrode is arranged between protection gaps of the upper discharge electrode and the lower discharge electrode, the distribution of an electric field between the protection gaps is changed, the maximal field intensity of the protection gap is increased, the thunder breakdown voltage of the protection gap is reduced, the long protection gap isdivided into two short protection gaps through the double-ring electrode, the thunder discharge path is confirmed, the dispersity of the gap discharge is reduced, and the anti-thunder effect of the insulator is improved.