The invention discloses a soldering lug for CAB soldering without soldering flux. The soldering lug comprises a brazing filler metal layer and skin layers wrapping the two sides of the brazing filler metal layer. The soldering lug is characterized in that the brazing filler metal layer comprises 5%-15% of silicon, 0.01%-1% of magnesium and 0.05%-0.15% of bismuth, and each skin layer comprises 3%-12% of Si and less than 0.10% of magnesium. According to the soldering lug, no core layer is arranged, the soldering lug is fully molten during soldering and flows into a region to be soldered, a soldering seam is formed and attractive in appearance, the quality of products is good, no residue exists, soldering flux pollution is avoided, and the soldering efficiency of the products is high; due to the fact that a three-layer structure is adopted, the very thin soldering lug can be made, the soldering lug is applied to complex components and occasions where the soldering portions are very narrow, such as CAB soldering without the soldering flux of aluminum alloys of part extrusion, part machining and the like, and therefore the soldering lug is extremely wide in application range; and meanwhile the soldering lug is extremely simple in structure, the manufacturing process is simple, the consumption of materials can be saved, and the manufacturing cost is lowered.