Galvanized steel is widely used in industry due to its excellent corrosion resistance. However,the zinc coating greatly reduces the welding process property of galvanized steel. As a new technique,laser welding is implemented to realize the joint of galvanized steel. There are two unique characteristics,zinc vaporization and zinc plasma,existing in deep penetration laser welding of galvanized steel. The key issue of laser welding of galvanized steel is the influence of the zinc vapor during the welding process. The reduction and elimination of the zinc coating evaporation are the fundamental methods to avoid the influence of the zinc vapor. Based on the key technology of laser welding of galvanized steel,varied welding processes and solutions are discussed to improve the quality of the laser welding,including specific processes,process parameters and simulation optimization,as well as the online monitoring and controlling during the welding process.