Abstract: In order to improve the yield of Monascus pigment and reduce the production costs, Monascus purpureus MY-03 was adopted to produce Monascus pigment in the liquid state fermentation, and the fermentation conditions were optimized by Plackett-Burman design and Box-Benhnken experimental design. The results showed that the optimum medium was composed of glucose 50 g/L, peptone 58.07 g/L, MgSO₄ 2 g/L, NaNO₃ 2 g/L, MnSO₄ 0.3 g/L, ZnSO₄ 0.1 g/L；and the optimum bottle load was 50.8 mL in a 250 mL flask, and the optimum inoculum volume was 10.0%（V/V）. The color value of Monascus pigment reached to 342.24±2.88 U/mL, increased by 86.9% than that in the basal medium, when the test fungi were incubated in 150 r/min and 30℃ for 7 d.

Key words: Monascus purpureus, submerged fermentation, Monascus pigment, Response Surface Methodology