The work aims to reveal the influence laws and mechanism of pulsed bias on structure, wear resistance and oxidation resistance of TiAlSiN films. TiAlSiN films were deposited on the surface of M2 high speed steel by cathodic arc ion plating technology with different pulsed bias parameters. Microstructures and properties of the films were characterized by SEM, XRD, 3D profilometer, metallographic microscope, scratch tester, friction and wear tester and high temperature oxidation test. The main phase structure of TiAlSiN films was AlN when pulsed bias was 50 V. When pulsed bias exceeded 75 V, the films were mainly composed of (Ti,Al)N phase and the preferred orientation of films on (200) was obvious. With the pulsed bias increasing to 150 V from 50 V, the films became more compact, surface roughness firstly decreased and then increased, but the adhesion of films firstly increased and then decreased. The main wear mode of TiAlSiN films was abrasive wear and the wear resistance was mainly affected by phase structure and film compactness. When pulsed bias was 100~150 V, the wear resistance was excellent. After oxidation for 4 h at 1000 ℃, the surface was oxidized to different extent, which was mainly affected by phase structure, compactness and surface porosity. Compared with (Ti,Al)N phase, the films with hcp-AlN phase was easier to be oxidized. The films were more compact and depth of the oxidized layer became shallower with the increase of bias. At the same time, as the number of pores increased, more Al2O3 clusters were formed on the surface. Under the pulsed bias of 100 V, TiAlSiN films have the most comprehensive properties, the adhesion is 46.7 V, the hardness is 3276HV0.025, the surface roughness is the lowest, the wear resistance is better and the oxidation resistance is the strongest at high temperature.