The work aims to reveal the effect of electromagnetic coil bias on the structure and properties of TiAlN coating under the coupling of electromagnetic and permanent magnetic composite magnetic field in the process of arc ion plating, and optimize the preparation process of TiAlN coating. Ti0.33Al0.67N coating with high Al content (TiAl target at%, Ti∶Al=1∶2) was deposited on the M2 high-speed steel substrate by arc ion plating technique. By changing the voltage of the electromagnetic coil, the microstructure, surface roughness, hardness, film/base bonding force and wear resistance of the coating were studied. When the coil voltage was less than 30 V in the range of 15 V to 45 V, the interior of the Ti0.33Al0.67N coating was dense. When the coil voltage was greater than 30 V, the interior of the coating became loose. When the coil voltage was 15 V, the surface roughness of the Ti0.33Al0.67N coating was at least 0.2 μm. With the increase of voltage, the hardness of Ti0.33Al0.67N coating increased, and the hardness of Ti0.33Al0.67N coating reached the maximum of 3866HV0.3 when the coil voltage was 45 V. As the coil voltage increased, the adhesion and wear resistance of the Ti0.33Al0.67N coating/base increased first and then decreased. When the coil voltage was 15 V, the binding force was 95.4 N and the wear rate reached the minimum of 1.62×10-15 m3/(N?m). When the coil voltage is small, as the coil voltage increases, the strength of the magnetic field acting on the cathode target increases, the speed of the cathode arc spot increases, the time for maintaining each arc spot shortens, the energy decreases, the ionization rate increases and the number of droplets splashed decreases. Thus, the coating structure becomes dense, the roughness decreases and the hardness and wear resistance increase. As the coil voltage increases further, the magnetic field strength continues to increase, the magnetic binding force of the arc spot movement increases, the movement radius of the arc spot contracts toward the center of the target and the accumulated time of the arc at a fixed position is longer, the ionization rate decreases, the droplets increase and overall performance of the Ti0.33Al0.67N coating declines.