In this study, MCM-41was synthesized from diatomaceous earth (SDE) as source of Si and cationic surfactant (CTAB) as a template through hydrothermal method. The MCM-41was characterized by instruments of x-ray fluorescence analysis (XRF), x-ray Diffraction (XRD), N2adsorption/desorption analyzer, fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) and high resolution transmission electron microscope (HRTEM). The experiment on heavy metal adsorption was applied so as to detect the property of the material. The research of microscopic structure illustrated the synthetic materials retain long-range order mesoporous structure. The surface area of MSM is 1060m2/g, the pore volume is 1.05cm3/g and pore diameter is 3.95nm. MSM has a good adsorption for heavy metal Cu2+. The result has a certain reference value for the comprehensive reuse of spent diatomaceous and the treatment of heavy metal.