Objective To improve the utilization of Poria cocos resources.Methods This paper employs cellulase and xylanase in combination with Monascus for the solid-state fermentation of Poria cocos, and measures the changes in the content of alkali-soluble polysaccharides, water-soluble polysaccharides, β-glucans, reducing sugars, total triterpenes, pachymic acid, and Monacolin K in fermentation products.Results Compared with the other five strains of Monascus, Monascus purpureus 250 Gy has more significant changes in the chemical composition of Poria cocos, among which the content of water-soluble polysaccharides reaches 61.99 mg/g after 6 days of fermentation by Monascus purpureus 250 Gy, which is 1.58 times higher than that of raw Poria cocos. Compared with the control group, the content of water-soluble polysaccharides in Poria cocos fermented by cellulase and xylanase with Monascus purpureus 250 Gy increases by 1.15 and 1.12 times respectively, the content of β-glucans by 0.81 and 0.70 times respectively, and the content of total triterpenes by 0.95 and 0.82 times respectively.Conclusion The combined treatment of the two enzymes with solid-state fermentation by Monascus purpureus 250 Gy has significant influences on the chemical composition of Poria cocos, serving as an effective method for enhancing the content of active substances in Poria cocos.