Abstract: Ferric sulphate was prepared by calcination and acidic leaching from iron stone,and the reasonable production process and operation conditions were gained. As a result of experiment, when calcining temperature, calcining time, concentration of sulfuric acid, acidic leaching time and liquid-solid ratio (quality ratio of sulfuric acid and ironstone) was found to be 800℃, 2h, 5mol/L, 3h and 6:1, respectively for the reaction, Leaching ratio of iron was the best. The process to prepare ferric sulphate above stated possess the advantages of cheap in the raw material, improvement economic benefits, social benefits and environmental benefits and treatment of wastes with process of wastes against one another.