Abstract: Laser-CMT hybrid welding is a new type of laser arc hybrid welding, which combines laser welding with cold metal transition welding（CMT）. Compared with traditional laser hybrid welding, it has extremely low heat input, more stable welding process, basically no spatter and the production efficiency and welding quality are improved. The principle and characteristics of laser-CMT hybrid welding were introduced, the development status and existing problems of welding joint,molten pool morphology, droplet transfer and weld formation in laser-CMT hybrid welding were summarized, finally the development direction and research focus of laser-CMT hybrid welding were summarized.