Sulphurized-nitrided compound layer is prepared on the surface of drilling pipe joint material 35CrMo steel by the application of ion nitriding and ion sulfurizing technology. Comparative study was made on anti-wear property under dry friction between original nitriding surface and sulphurized-nitrided compound surface. With dry friction, high-hardness nitriding coat would further intensify the wear, because contact surface of friction pair is lack of lubrication; and sulphurized-nitrided compound coat has better anti-wear property, just because there is a layer of solid lubrication coat of ferrous sulfide on the surface.