Abstract: A method for preparing the high acid-consuming-capacity dried aluminium hydroxide powder by the use of alum and soda or other alkali substance as raw material is described. 1) The best results were obtained by using soda as raw material for preparing the alkali solution. 2) The alum solution was added to the alkali solution until pH 5.5-6.5 was reached. 3) The sulfate was removed almost completely by washing with potassium bicarbonate solution(0.4%) before drying. 4) The aluminium hydroxide gel can be dried completely under 100-105℃(ca. 6 hrs.) without influencing the antacid activity. 5) The highest acid-consuming-capacity of the dried powder of aluminium hydroxide gel(free from any free alkali) was determined to be 315.9 ml, i.e. one gram dried sample will neutralize 315.9ml 0.1N HCl.