Abstract: The hydrazone functionalized MCM-41 molecular sieve was prepared with 2-oxo-propionic acid salicyloyl hydrazone and MCM-41 molecular sieve as reactants, and was characterized by infrared spectroscopy and thermogravimetric analysis. Its adsorption proporties were evaluated and the adsorption mechanism was discussed. The results showed that when the adsorption time was 30 min, the adsorption temperature was 20℃, the addition of modified MCM-41 was 0. 08 g, and the p H was 6~7, the adsorption efficiency of Cu²⁺ was the best; the removal rate of Cu²⁺ was up to 97. 58% under the optimum condition.