Cu/ZnO/Al2O3/ZrO2 catalyst used in diethanolamine dehydrogenation was synthesized via a coprecipitation process with copper nitrate, zinc nitrate, aluminum nitrate and zirconium oxynitrate as reactants, using sodium hydroxide as precipitation agent, and various kinds of copper-based catalyst were characterized by means of physical adsorption (BET) and X-ray diffraction (XRD), and the influence of different ratio of ZnO and Al2O3 in the catalyst were discussed. The results show that, Cu/ZnO/Al2O3/ZrO2 catalyst which add ZnO and Al2O3 simultaneously have a big specific surface area, and have an amorphous structure. The conversion of diethanolamine was up to 100%, the yield of iminodiacetic acid was 95.61% under the suitable catalyst conditions of 30% sodium hydroxide, temperature 160 ℃， pressure 1.0 MPa.