Abstract: In the experiment, the laser -MIG hybrid welding method was adopted to systematically optimize the laser power, welding current, optical wire distance and the interaction among the three factors in the laser -MIG welding process of aluminum alloy parts for automobiles. The effects of interaction of various parameters on the penetration depth and relative melting rate of welded joints were also studied. The experimental results show that the laser power has a significant effect on the joint penetration without considering the influence of the optical distance while the welding current barely has influence on the penetration depth of the joint. However, on the premise of not considering the impact of welding current, the effects of the laser power and the optical fiber distance on the joint penetration are both significant. Additionally, without considering the influence of the optical wire distance and the welding current, the penetration depth of the joint increases significantly with the increase of the laser power.