Abstract: When α-amylase acts on starch, it cuts the α-1, 4-glycosidic bond inside the molecule to generate reducing sugar and dextrin. Inhibition of α-amylase activity can affect the increase of blood sugar level in human body and reduce the risk of hyperglycemia and obesity. Studies have found that in addition to antioxidant activity, black bean protein can also inhibit α-amylase activity, and 7S globulin has better inhibitory activity on α-amylase and α-amylase. In order to explore the inhibitory activity of 7S globulin on α-amylase, the following experiments were designed. The optimal extraction process of 7S globulin was determined by using design-Export 8.0 software, with α-amylase inhibition rate as index, solid-liquid ratio, extraction pH and sodium chloride addition as influencing factors. The optimal extraction conditions were liquid-solid ratio of 13∶1, pH 4.8 and sodium chloride content of 0.16 mol/L, under which the inhibitory rate of 7S globulin on α-amylase could reach 70.51%. It was concluded that the inhibitory rate of 7S globulin on α-amylase showed a positive linear correlation when the concentration was 0-20 mg/mL. In the range of 30-60 ℃, 7S globulin had a good inhibitory activity on α-amylase. In addition, 7S globulin is a thermosensitive protein. 7S globulin had good acid-base tolerance in the pH range of 3-9, and was completely inactivated when pH drops to 2. Starch mass concentration had little effect on the inhibitory activity of α-amylase, which might be related to the inhibitory type of 7S globulin.According to this experimental study, it was shown that 7S globulin had a good inhibitory effect on α-amylase, and different treatment conditions can affect the activity of this globulin, and the experimental results can provide reference value for improving the utilization of 7S globulin resources in black bean.