Abstract: In this paper,the research status,development trend and existing problems of the related technologies at home and abroad were systematically expounded and analyzed from aspects of the molten pool behavior,plume characteristics,the suppression of welding defects,the development and engineering application of the welding process. For laser welding of medium steel plate,how to ensure the weld quality was one of the key problems whether the laser welding could get application when using 10 kW level fiber laser. And the existence of the plume was a major factor affecting the stability of laser welding. The influence of plume on laser energy could be reduced by the method of side blowing,topical negative pressure and vacuum method. In addition,weld collapse and bottom hump were also the main technical problems hindering the application of 10 kW level laser welding technique. Better weld formation could be achieved by changing the welding attitude,adopting electromagnetic support system,bottom pressure method or forced formation on the back of the weld.