A multi-component alloy grade with liquidus temperature lower than 500 ℃ was obtained by adding Ge and Mg elements on the basis of Al-Cu-Ag alloy, and the melting characteristics, as cast structure, tensile strength and section morphology of the alloy solder were studied. The results show that the solidus-liquidus temperature of the new designed Al-Cu-Ag-Ge-Mg solder is 468 – 491 ℃; in the vacuum environment, when heated to 530 ℃ for 5 minutes, the surface of 5A05 aluminum alloy has a good wetting spread phenomenon. Under the same conditions, the tensile strength of the joint obtained by brazing is more than 50 MPa by tensile test at room temperature; combined with the observation and analysis of section morphology. The addition of Ge can effectively reduce the solidus liquidus temperature of solder, and exist in the as cast structure and soldering seam with AlGe and MgGe. The presence of Ge element can inhibit the effect of other elements of the solder and Mg in the base metal, and alleviate the corrosion phenomenon between the solder and the base metal.