Physical and high speed centrifugation methods were used to purify the bentonite sample from Riyuelei mine in Xiazijie,Xinjiang,and the main factors influencing its purification,such as liquid-solid ratio,stirring time,the speed and time of centrifugation,were investigated.The optimum purification conditions of purifying the bentonite were determined through orthogonal experiments.After purifying the quality of bentonite was greatly improved,the expansion volume,montmorrilonite content and cation exchange capacity were enhanced from 53.8 ml/g,68.5% and 64.9 mmol/100g to 89 ml/g,96.6% and 98.4 mmol/100g,respectively,moreover,the contents of Ca2+,Mg2+ were decreased in some degree.The single point BET specific surface area of bentonite after purifying increased from 57.99 m2/g to 71.14 m2/g,so the adsorption capability was obviously improved.