In order to obtain the best extraction process of flavonoids (TF) and antioxidant activity, hypoglycemic activity, explore the influence of five extraction process on the TF extraction(Ultrasound-assisted extraction, acid extraction, enzymatic extraction, hot water extraction, hot alcohol extraction), optimized the extraction process through single factor experiment and response surface experiment; determination and analysis of the distribution and contents of seven major flavonoid glycosides by HPLC;and further study the correlation between TF and in vitro antioxidant activity (DPPH clearance ability, ABTS radical clearance ability, hydroxyl radical scavenging ability, reducing ability) and in vitro glucose reduction ability of α-glucosidase. The results showed that ultrasound-assisted extraction had the highest TF content, and the response surface was optimized for the best extraction process: temperature 68 ℃, time 23 min, ethanol volume fraction 24 %, liquid ratio 63:1 mL/g. Under this condition, the TF content was 34.85 mg RT/g (Equivalent rutin RT mass per gram of TF compound expressed); the HPLC identified 7 major flavonoids in TF, The most abundant flavonoid compounds in the TF were quercetin-3-O-palmitoyl-7-O-rhamnoside and quercetin with 3.897 mg/g and 2.874 mg/g; TF mass concentration and DPPH clearance capacity, ABTS radical scavenging ability, hydroxyl radical scavenging ability and reducing ability showed significantly positive correlation, and the hypoglycemic capacity of α-glucosidase could reach 92.6 %.