Abstract: The single-factor adsorption of mixed waste water with Cr3+ and methylene blue was studied by means of oscillating adsorption.The results showed that MCM-41 and Al-MCM-41 mesoporous molecular sieves prepared from fly ash had better adsorption effect on the mixed waste water.The adsorption removal rate of Cr3+ and methylene blue in the mixed waste water reached 83.00% and 99.27%,respectively.The saturated adsorption capacities were 1.544mg/g and 2.639mg/g which all met the Langmuir adsorption isotherm model.