To study the effects of magnetic field stirring on the laser metal deposition (LMD) parts, a device of rotating magnetic field is designed and introduced to the LMD processes of titanium alloy. The microstructure of the laser deposition layers is characterized and the deposition layers′ microhardness is tested. The results show that the convection in the laser melting pool caused by magnetic field makes the top cross-section of single pass concave-shaped. With the higher rotating speed of magnetic field, the α lamellar is finer, and the micro-hardness of deposition layers is much harder which can be 440 HV0.1. It indicates that rotating magnetic field intensifies the convection in the pool and increases its cooling speed, which leads to finer microstructures and better mechanical property.