For determining the method of photometric used the reaction of Cu with N,N'-bis-(3-phenilazopentadion-2,4)ethylene diimine with 1,10-phenantrolin, 2,2’-dipiridil and ethylene diamine. The complex product which is getting from the reaction of Cu with reagents shows and prove that, by existing amines, we get different ligand complex and at this time, shift to absorption spectrum happens bathochrome replacement and in the compare with the same ligand’s complex getting maximal complex which shift to acidic medium. The influence of the concentration of the reactants, the time the formation mixed-ligand complexes and determine their stoichiometry in various ways. The developed method was applied to determination of trace copper in copper-based alloys