Objiective: In order to improve the extraction efficiency of polysaccharide from Ampelopsis grossedentata. Methods: Ultrasound-assisted enzymatic extraction method was used in this study to optimize the extraction process of polysaccharide from Ampelopsis grossedentata. The effects of ultrasound temperature, ultrasound extraction time, enzymolysis pH, ultrasound power and the addition of complex enzyme on the extraction efficiency of polysaccharide from Ampelopsis grossedentata were investigated by single factor test. And the significant factors, including enzymolysis pH, ultrasonic power and he addition of complex enzyme were by Plackett-Burman test. The optimal extraction conditions were obtained through the steepest climbing test and Box-Behnken test. Results: The optimal extraction conditions were as follows: the value of pH 4.30, ultrasound power 104 W, the addition of complex enzyme 1.20%, ultrasonic time 40 min, ultrasonic temperature 50 ℃. Under these optimized conditions, the yield of polysaccharide from Ampelopsis grossedentata was （7.22±0.06）%. And compared with that of hot water extraction, ultrasound extraction and complex enzyme extraction method, the yield was increased by 106.83%, 86.35%, 54.46%, respectively. Conclusion: Ultrasound-assisted enzymatic extraction method can obviously im-prove the yield of polysaccharide from Ampelopsis grossedentata.