Abstract: In order to improve the utilization efficiency of Aluminum sludge and make it better used in the remediation of eutrophic water body, we carried out a series of phosphorus adsorption experiments in water by dewatered Aluminum sludge (DAS) from water supply plant as adsorptive material. The influence of DAS dosage and particle size, pH and phosphorus concentration in water samples on the absorption process were studied. The Langmuir and Freundlich isothermal adsorption equation model were used to fit the absorption process. Box-Behnken Design（BBD）model in response surface methodology (RSM) was used to evaluate the influence significance of several variables, including adsorption time, pH and DAS dosage and their interaction effects. In addition, we have optimized the experimental conditions by the BBD model. The results showed that the four factors mentioned above all have some influence on the adsorption process. The fitting effect of Langmuir isotherm adsorption equation was better. The theoretical saturated adsorption capacity of phosphorus by aluminum sludge is 1.487mg/g (at 298K). The response surface analysis results showed that the amount of aluminum sludge had the most significant effect on the adsorption, and the interaction effects between pH and reaction time were the strongest. When the phosphorus concentration in the water is 10mg/L, the optimum technological conditions are as follows: the aluminum sludge dosage is 12 g / L, pH is 4.5 and reaction time is 48 h, and the corresponding maximum removal rate is 92.38%.