Abstract: The protein was extracted from Tibetan Huidouba for the first time with ultrasonic-assisted extraction.The extraction process was optimized by response surface methodology based on the results of single factor experiments. The results showed that the optimal conditions were as follows:ultrasonic power 800 W,ultrasonic time 52 min,temperature 57℃,p H7.5 and the liquid-solid ratio 54 ∶1m L/g. Under the optimal extraction conditions,the extraction rate of Huidouba protein was 52.66%,and it was only a difference of 0.07% with the theoretical value which was 52.59%. The purity of the Huidouba-protein was up to 56.75% after the processes of centrifugation,microfiltration and dialysis. It had been proved that the Huidouba crude protein had inhibition effect on α-glucosidase(AGD),and its value of inhibitory activity IC50 was about 18mg/m L.