Abstract:Phellinus igniarius strain S1 mutagenized with laser and UV was chosen to study the conditions of liquid fermentation by singlefactor experiment. Based on quadratic orthogonal rotation combination design,the optimum conditions were determined as media amount of 120 mL with inoculum size of 17 mL,and fermentation temperature of 26 ℃ at rotate speed of 135 r·min-1. According to verification experiment, the actual mycelial yield was at the range of (24.47±0.80) g·L-1. The compact fermentor experiment was conducted based on the designed optimum conditions. The results show that the optimum fermentation conditions were with stirring speed of 180 r·min-1 at temperature of 29 ℃ with air flow of 6 L·min-1.The mycelia and expolysaccharide yields can reach the range of (68.23±2.51)g and (10.23±0.35)g, respectively.