Abstract: In this paper,the Cerasus leaves were taken as the research object,the total flavonoids of Cerasus leaves were extracted by ultrasonic method,and their antioxidant capacity was studied. The optimum extraction conditions of total flavonoids from Cerasus leaves were as follows:60% ethanol solution,1:35 g/mL ratio of material to liquid,50 W of ultrasonic power,70 ℃ of extraction temperature,and 50 min of extraction time. Under this condition,the extraction rate of total flavonoids from Cerasus leaves reached 14.74%. The results of the antioxidant ability of Cerasus leaves showed that the higher the mass concentration of total flavonoids extract from Cerasus leaves was,the stronger the scavenging abilities of ·OH,DPPH· and NaNO₂ were. When the concentration of total flavonoids in Cerasus leaves was 1.2 mg/mL,the scavenging rate of ·OH reached 79.12%. When the concentration of total flavonoids in Cerasus leaves was 0.5 mg/mL,the scavenging rate of DPPH· reached 94.60%. When the concentration of total flavonoids in Cerasus leaves was 1.4 mg/mL,the scavenging rate of NaNO₂ reached 66.55%. Therefore,the total flavonoids of Cerasus leaves had good antioxidant activity,which provided a theoretical basis for the research and development of total flavonoids of Cerasus leaves.