By means of the flame braze, the welding problems on Aluminum alloy(5A06)and low carbon steel Q235) were mainly researched in this paper. The welding technology adopted in this paper is that a hot-dipped Aluminum coating of ZL102 Aluminum alloy was firstly performed on the surfaces of low carbon steel, then the layer of hot-dipped aluminum and aluminum alloy were welded by the shape of the lap joint. Through the analysis of the microstructure and tensile property of welded joint after the experiment, the experimental results expressed that good welded joint can be attained by application of flame brazing. Fracture location of the joint specimens appears in the coating layer by means of tensile test. The results show that the bond strength of the coating layer was less than that of the brazing seams..