Abstract: Objective:To optimize the ultrasonic-assisted extraction conditions of α-terthienyl in Radix Echinopsis by the response surface analysis methodology. Methods:The yield of α-terthienyl was selected as investigation index, choosing the power of ultrasonic, extraction temperature and extraction time as random factors, and three-factors-three-levels Box-Behnken central composition designed to investigate the effect on the yield ofα-terthienyl. Results:The optimal conditions were ultrasonic power of 350 W, extraction time of 42 min and extraction temperature of 41℃. Under these conditions, the predicted value of 86.5% was inosculated with the actual value of 85.1%. The relative error was only 1.6%. Conclusion:These methods were feasible for optimizing extraction processing and would efficiently improve the extractions of α-terthienyl in Radix Echinopsis.