Lightning arrester

The utility model discloses a lightning arrester comprising a vertical discharge system and a multi-cavity system, the vertical discharge system is arranged on a synthetic sheath of a lightning arrester, electrodes comprise an upper electrode and a lower electrode, the upper electrode and the lower electrode are respectively arranged at intervals along the axial direction of the lightning arrester, the upper electrode is located above the lower electrode, and the multi-cavity system is located above the lower electrode. A discharge gap is formed between the upper electrode and the lower electrode; a multi-cavity system is annularly arranged on the synthetic sheath of the lightning arrester; a plurality of spherical electrodes are arranged along the side wall of the synthetic sheath in an annular array, an arc extinguish chamber is arranged at the position of every two adjacent spherical electrodes, the arc extinguish chambers are located on the synthetic sheath, each arc extinguish chamber is a cavity with a