Suitable conditions for polysaccharide production in submerged culture by Coprinus comatus Ft. CC-8810 were: glucose 40g, Soybean cake powder 30g, yeast extract powder 5.0g, bran 30g, KH_2PO_4 1.0g, MgSO_4?7H_2O 0.5g, tap water 1L, pH5—6, 28℃, 160r/min. Seed culture grown in shake flask for 4 days were inoculated into 1.5L fermentor. After 5—6 days the fermentation ended up with decreases in pH to 4.9—5.0 and in reducing sugar to 1.2%. 45.1g(dry Wt.)/L hyphae and 3.6g/L polysaccharide were obtained.