The ultrahigh pressure extraction technology was used to extract polysaccharides from Polygonatum cyrtonema Hua. The single factor experiment and response surface method were applied to obtain optimal process parameters. Furthermore, the antioxidant activity of polygonatum polysaccharides was investigated. The results showed that the optimal extraction conditions were as follows: pressure 255 MPa, particle size of raw material 40 mesh, ratio of raw material to extraction agent 1∶17 (material refers the mass of the raw material, unit g；liquid refers to the volume of the extractant agent, unit mL ), extraction time 9.5 min, extraction temperature room temperature ，and extractant agent (water). Under these conditions, the extraction rate of polysaccharides was 25.01%. While the traditional decocting method had an extraction rate of polysaccharides of 19.83% at 100℃ for 90 min, which indicated that ultrahigh pressure extraction technology was more effective technology for extracting polygonatum polysaccharides. The scavenging ability of polysaccharides (mass concentration 1 g/L) toward 1, 1-diphenyl-2-trinitrophenylhydrazine (DPPH) free radical reached 34.14%.