The invention relates to a method for preparing superfine 
aluminium silicate by 
bentonite, which takes the mineral 
powder of the 
bentonite as a 
raw material and comprises the steps of 
pickling, purifying, alkaline leaching, synthesizing, washing and 
drying. In the 
pickling step, acid liquor is added according to the weight ratio of 1:2.5 to 5.5 of the mineral 
powder of the 
bentonite to the acid liquor, and the mineral 
powder of the bentonite and the acid liquor react for 2 to 6 hours at the temperature of 80 to 105 DEG C; in the purifying step, 
potassium permanganate and 
manganese sulfate which have the weight ratio of 0.7:1 are added after the pH value of 
pickling filtrate is regulated to 3 to 4 by using a 
sodium hydroxide solution, the adding quantity of the 
potassium permanganate and the 
manganese sulfate is 1 to 3 percent of the weight of the pickling filtrate, and an 
aluminium salt solution is obtained by 
processing; and in the alkaline leaching step, the 
sodium hydroxide solution is added into a pickling 
filter cake according to the weight ratio of 1:2.5 to 5.0 of the pickling 
filter cake to the 
sodium hydroxide solution, and the pickling 
filter cake and the 
sodium hydroxide solution react below the boiling temperature to obtain water glass. In the synthesizing step, the 
aluminium salt solution and a water glass solution react to obtain the superfine 
aluminium silicate by separating, washing and 
drying. The invention has the characteristics of low production cost, low 
energy consumption and good economic benefit.