Based on the characteristics of molten pool flow behavior of laser penetration welding, the laser penetration welding technology of layered bimetallic composites is proposed, which can realize the onetime welding forming of layered bimetallic composites, reduce the dilution of base metal to clad metal and damage its functional properties, which has great potential in improving the welding quality of layered bimetallic composites and promoting its application power. In this paper, the research results related to the welding of layered bimetallic composites are reviewed. The principle and characteristics of laser penetration welding technology and the influence of process conditions on the microstructure and properties of welded joints are expounded. The future development direction of laser penetration welding is prospected.