In order to make the low-cost and high-quality feed from brewers' spent grains,using the distillers' grains as an auxiliary material,the fermentation technology of Trichoderma viride was investigated with an aerobic fermentation installation and with the methods of Plackett-Burman and response surface.The fermentation of Rhodopseudomonas palustri was adopted to increase the content of protein after Trichoderma viride fermentation.With the ratio of dried brewer grains-to-dried distillers' grains set at 2.67∶ 1(w/w),the mixed grains-to-water ratio set at 1∶ 2.88(w/w),the inoculum concentration at 9.5 %(w/w),the initial pH at 5.0,the early fermentation at 30℃ for 4.82 d,the later fermentation at 50℃ for 2.5d,the thickness of feedstock layer at 9 cm,and the air volume at 83.2 mL/min,the crude cellulose content of mixed grains was decreased from 17.2 to 9.9 %(w/w).After the second fermentation of Rhodopseudomonas palustri,the true protein content of mixed grains was increased from 16.1% to 38.4%(w/w),the content of crude protein was increased from 21.5% to 43.9%,the crude cellulose content of mixed grains was decreased from 17.2% to 5.9%(w/w),the fat content of mixed grains was increased from 5.7% to 8.1%(w/w),the crude ash content of mixed grains was increased from 6.6% to 7.8%(w/w),the total phosphorus content of mixed grains was increased from 0.6% to 1.3%(w/w),and the water content of the grains was 9.8%(w/w).The six indexes satisfied the China standard for tilapia's fingerling(SC/T1025-2004).