Abstract: Collybia albuminosa has higher levels of biological polysaccharide that has various physiological functions such as anti-tumor and enhancement of body immunity, but due to the high requiments of its own growth conditions and the change of ecological environment, the content of Collybia albuminosa biological polysaccharide cultured by traditional method is lower. On the basis of single factor experiments in biological polysaccharide content and bacterial wet weight per unit volume, the best culture conditions including cultivation time,temperature, initial p H value were optimized by response surface method with Collybia albuminosa biological polysaccharide content as index. The results showed that the best culture conditions were as follows: glucose2.50%, peptone 0.25%, culture time 7 days, culture temperature 27.6 ℃, and initial pH 7.0. The content of polysaccharides reached 2.71 g/L under the above conditions. Which provides theoretical basis for the improvement of biological polysaccharide content by liquid culture of Collybia albuminosa.