Abstract:To investigate the mechanism of bi-directional fermentation between edible fungi and medicinal substrate，based on as fermented by Monascus purpureus strains，with rich in flavonoids of Ginkgo biloba medicine juice as fermentation substrate，the effects of different carbon sources，nitrogen sources，inorganic salts，growth factors，liquid amount，fermentation time and initial pH value on the biomass of Monascus purpureus and the total flavonoids juice content in Ginkgo biloba leaves were studied by single factor experiment.And Monascus purpureus was optimized by using orthogonal experiment and Ginkgo biloba leaves to fermentation conditions，the results showed that in Ginkgo biloba medicine juice medium fluid volume 85 mL，quantity of 10% ，initial pH value of 5，inorganic salt FeSO4conditions，the optimal combination for fermentation：glucose concentration 4%，peanut powder concentration 1.5%，concentration of KH2PO40.1%，MgSO4concentration 0.12%，150 r/min，（28±1）℃ 11 d.Under this combination，the total flavonoids content in the bi-directional fermentation system reached 0.074 mg/mL，100%higher than the control group without Monascus purpureus fermentation.The biomass of Monascus purpureus was 13.26 g/L，76.47%higher than that of the control group before optimization.Therefore，bi-direction fermentation of Monascus purpureus and Ginkgo biloba leaves could increase the total flavonoids content of Ginkgo biloba leaves and promote the growth of Monascus purpureus biomass.