In this paper,ophiopogon japonicus crude polysaccharide was extracted by hot water and ultrasonic extraction, then purified by DEAE-cellulose52 cellulose column chromatography and Sephacryl S-300 gel column chromatography. Homogeneous polysaccharide WPOJ-DS extracted with hot water and UPOJ-DS extracted by ultrasound were obtained. The structures of WPOJ-DS and UPOJ-DS were characterized by high performance liquid chromatography,gas chromatography,infrared spectroscopy,partial acid hydrolysis,methylation an...