The work aims to improve the extraction rate of Chinese yam polysaccharide efficiently and quickly and obtain Chinese yam polysaccharide with better performance. With iron stick yam planted in Lutu (black, hard, coarse but non-sticky soil) as the raw material, the effects of extrusion temperature, frequency of screw rotating motor, moisture content and feeding motor frequency on the extraction rate of Chinese yam polysaccharide (CYP) were studied by single factor experiment, Box-Behnken design and response surface methodology, and the properties of Chinese yam polysaccharide after extrusion were studied. The regression model was highly significant, and the optimum extraction conditions were determined as follows:extrusion temperature was 130℃, frequency of screw rotating motor was 26 Hz, moisture content was 20%, and feeding motor frequency was 16 Hz. Under these conditions, the extraction rate of extruded Chinese yam polysaccharide (E-CYP) was greatly increased, reaching 44.97%, which was 31.67% higher than that of non-extruded Chinese yam polysaccharide. It was found by scanning electron microscope that the surface of Chinese yam polysaccharide after extrusion showed a large number of irregular pore structures, and the overall structure was relatively loose. The antioxidant performance test showed that E-CYP showed better antioxidant activity than CYP. With the increase of polysaccharide concentration, the scavenging ability of hydroxyl radical and superoxide anion radical increased gradually, among which the scavenging ability of hydroxyl radical was the highest, accounting for 58.20%, indicating that the extruded Chinese yam polysaccharide had better antioxidant activity. The high-efficiency extrusion extraction method of Chinese yam polysaccharide with high yield and strong oxidation resistance are obtained, which provides a theoretical basis for the high-value utilization of Chinese yam polysaccharide in active packaging and as a homology of medicine and food.