Abstract: In order to obtain brazing material for copper and aluminum brazing with good performance, Zn15Al5CuxIn (x = 0,1,3,5) brazing material is prepared by adding different quality In. Through scanning electron microscope (SEM), energy disperse spectroscopy (EDS) and other analytical testing methods, the spreadability of Zn15Al5CuxIn solder on Al, Cu plates and the change of interface composition were studied. The results show that the addition of an appropriate amount of In can significantly improve the wettability of Zn15Al5Cu solder on Cu and Al base metals. When the amount of In added is 5%, the Zn15Al5Cu5In solder has the largest spread area on the Al base material, reaching 251 mm², which is 42.6% higher than that of the base solder; When the In addition amount is 3%, the Zn15Al5Cu3In solder has the largest spread area on the Cu base material, reaching 110 mm², which is 69% higher than the base solder.