To reduce the wear of both drilling pipe joints and casing pipes, 35CrMo steel used in drilling pipe joints was successively treated by ultrasonic surface processing and nitridingsulphurizing treatment. Surface morphology, roughness, composition, hardness, and phase structure, were characterized by optical profilometer, scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), microhardness tester, and Xray diffraction (XRD). The wear properties of 35CrMo drilling pipe joints and casing pipes were evaluated on a ringblock wear tester under lubrication with waterbased drilling fluid. The results show that the ultrasonic surface processing can remarkably reduce the surface roughness of 35CrMo samples both with and without sulfurnitrade treatments. The samples with both the surface nanocrystallization and nitridingsulphurizing treatments have higher surface hardness, obviously improve the antiwear properties of 35CrMo steel, and lower the wear rates of the casing pipe samples. At the same time, worn surface morphologies of both drilling pipe joints and casing pipes are evidently improved.