Abstract: To study the optimization of culture conditions on the extracellular polysaccharides Coriolus versicolor， the response surface methodology （RSM） based on the single factor tests were applied. According to regression analysis， the optimal culture conditions were culture time 24 days, broth content 676 mL, and initial pH 51. In order to get the purified polysaccharide， alcohol precipitation and DEAE Sepharose CL6B purification were used. The polysaccharide was identified the uniform component by PAGE. The HPLC results showed that the components of monosaccharide contain at least glucose and xylose， without peptides.