Laser welding using a laser beam as a heat source a heat processing, it is compared with the electron beam, ion beam and general machining, has many advantages: (1) the laser focal spot of the laser beam is small, high power density, high melting point, high strength alloy can be welded material. (2) Laser welding is the non-contact machining, tool wear and tool exchange. The energy of the laser beam is adjustable movement speed adjustable, can be a variety of welding process. (3) laser welding high degree of automation, computer control, welding speed, high efficiency, convenient for any complex shape welding. (4) laser weld heat affected zone is small, small material deformation, no follow-up processes to deal with. (5) Laser welding through the glass in the vacuum vessel of the workpiece and the workpiece in a complex structure of an interior location. (6) a laser beam is easy to guide, focus, and transform each direction. (7) laser welding and electron beam processing comparison, do not require strict system of vacuum equipment, easy to operate. (8) laser welding high production efficiency, stable quality and reliable, economic and social benefits.