The invention relates to a method and a device for reducing arc plasmatron electrode ablation. The arc plasmatron mainly comprises a cathode, an anode, an insulation member and an outer sleeve. Mechanical knurling, wire drawing, sand blasting and shot blasting for a surface of an arc plasmatron electrode are carried out, the electrode surface appearance, a stress status and the microscopic organization and the crystal phase structure are changed, so the energy state of the surface of the electrode is changed, the attachment reaction energy of arcs attached to the surface of the electrode is influenced, or micro attachment points are scattered, and thereby electrode ablation of the arc plasmatron can be reduced.