Abstract:CuSO4?5H2O crystal was prepared from extraction solution of leaching copper-cobalt ore by acid-precipitation method. The results show that crystallization rate of CuSO4?5H2O reaches first peak value about 80% in three hours and then drops to about 70% in five hours, and crystallization rate rises with increase of reaction time after 5 h. Crystallization rate rises with drops of solution temperature during crystallization. Crystallization rate first rises and then drops with increase of dosage of sulfuric acid. Crystallization rate rises with increase of Cu2 concentration in copper strip liquor. Crystallization rate is 80% above under the optimum conditions including room temperature, sulfuric acid dosage of 30 mL for 100 mL copper extraction solution, and precipitation time of 3 h. Recycled solution after crystallization of copper sulfate can be cyclic utilized without environment pollution.