n the early 1980s, kilowatt lasers were successfully used in industrial production. At present, laser welding machine production lines have appeared in the automobile manufacturing industry on a large scale, becoming one of the remarkable achievements of the automobile manufacturing industry. As late as the 1980s, European automakers took the lead in using laser welding technology to weld metal panels such as roofs, bodies, and side frames. In the 1990s, the United States introduced laser welding into the automobile manufacturing industry. Although it started late, it has developed rapidly. In Italy, laser welding is used for the welding and assembly of most steel plate components, while in Japan, laser welding and cutting processes are used for the manufacture of body panels. Laser welding of low-strength steel components has been increasingly used in automobile body manufacturing due to its outstanding performance. According to statistics from the US metal market, by mid-2002, the annual consumption of laser welded steel structures will reach 70,000 t1998, three times a year. According to the characteristics of high-volume and low-automation in the automobile industry, laser welding equipment is developing in the direction of high-power and redundant channels. In terms of technology, Sandia National Laboratory and Pratt Witney jointly carried out research on adding powder metal and metal wire during laser welding. The automatic laser welding machine of the Bremen Institute of Applied Beam Technology has conducted a lot of research on the laser welding of aluminum alloy frames. It is believed that adding fillers in the welding seam will help eliminate thermal cracks. The handheld laser welding machine improves the welding connection speed and solves the tolerance problem. The developed production line has been put into operation in the factory.