Based on the different proportion of aluminum in the body,the surface treatment technology of steelaluminum hybrid body materials is innovatively studied.the results show that when the surface of steel-aluminum hyb rid body material is treated by traditional phosphating process,a uniform and dense phosphating film is formed on the surface of cold rolled plate,galvanized plate and aluminum plate,and the slag production of aluminum plate is less than 4 g/m^(2);when the post-treatment process is applied to the surface treatment of steel-aluminum mixture,the aluminum plate does not form a phosphating film in the phosphating bath solution of the post-treatment process,but a passivation film is formed on the surface after the passivation process.The amount of slag produced by aluminum in the phosphating solution is less than 0.5 g/m^(2);When the surface of the steel-aluminum mixed material is treated by the non-phosphorus forming process,the steel-aluminum mixed body material can form a Zr film in the same tank,and the amount of residue formed by all plates is less than 0.2 g/m^(2).