A cost-effective molasses medium was developed for enhancing the biomass production of biocontrol yeast Rhodosporidium paludigenum.The optimum media components were 9% cane molasses and 0.2% yeast extract.The fermentation conditions were optimized through single-factor experiments and an orthogonal test.The highest biomass production of 13.50 g/L could be obtained at following conditions:the initial pH 8.0,the inoculums 3%(v/v),medium volume 45 mL/250 mL and a fermentation time of 56 h.Further research is worthwhile in this field.