Abstract: This paper research the absorb performance that the bentonite by Al³⁺ modify to including phosphorus waste water.It is influenced that the bentonite absorbs performance after investigating such factors as pH,the temperature,time,absorbent reacting,etc.the result shows:Include 10% Al³⁺ of bentonite not absorbing by function of getting rid of for stronger one about phosphorus.In pH=9 and mix and absorb 40min under 300r/min condition,when the consumption of the Al³⁺ modify bentonite is 5g/L,is up to 23.4mg/g to the absorbing amount including phosphorus waste water of 13mg/L;Is not greater than the waste water of 7mg/L to phosphorus content,its getting rid of rate is greater than 95.5%,the content of remaining phosphorus is smaller than 0.5mg/L in the waste water,has reached the first class standard that the waste water of our country discharges synthetically.