In view of problems of laser spot welding of aluminum, a precise control wire filler is built, and the feasibility of laser spot welding of aluminum alloy with filler wire and the influences of filler wire angle, wire feed volume, delay time are analyzed. Experimental results show that the filler wire method can improve the defects of laser spot welding of aluminum. The angle of the filler wire is the key factor which influences the stability of the process of the melt wire into the pool. When the wire is feed at an angle of 30° or so, the feed process is most stable. The delay time is one of the main factors which determine the pool size. When the delay time is too short, the filler wire can be easily accumulated on the surface of the specimen. The volume of the wire feed into the pool is directly related to the improved effect of collapse.