Excess water phosphorus will cause phytoplankton blooms and result in eutrophication, so the decontamination of phosphorus becomes an urgent task in China. In this paper, adsorption of phosphorus was investigated by using industry expanded vermiculite collected in Henan Province. In this paper, phosphorus adsorption isotherm was examined, and the effects of pH value, adsorption time and dosage of vermiculite were investigated. During the agitated batch experiments, the leaching behavior of metals in vermiculite was studied and the reaction mechanism was revealed. The results show that precipitation reaction and ion exchange with iron and aluminum elements in vermiculite are the dominating mechanisms of phosphorus removal. With correlation coefficient of 0.985 1 and saturation adsorption capacity of 2.76 mg/g, Langmuir isotherm fitted the data of phosphorus adsorption on vermiculite very well. Finally, significant influence of pH value on phosphorus sorption was observed within the pH range of 3～9 in the tested sample system.