The invention discloses freshwater fish feed and a preparation method thereof. The feed comprises the following materials in percentage by weight: 5%-17% of import fish powder, 8%-22% of flour, 3%-16% of potato starch, 3%-18% of beer yeast, 5%-15% of bean pulps, 5%-15% of peanut pulps, 5%-10% of rape seed cakes, 2%-8% of corn powder, 3%-9% of cooked egg protein, 5%-8% of dried meat floss powder, 1%-2% of liquid phytase, 1%-3% of non-starch polysaccharase, 0.5%-1.9% of glutamine, 1%-2% of microecological preparation and 1%-3% of immune polysaccharides. The preparation process comprises a crushing step, a mixing step, a pelletizing step and a spraying step. The freshwater fish feed has the beneficial effects of being capable of well satisfying the nutrition needs of freshwater fish, improving the immunity of the freshwater fish, prompting intestinal absorption and improving the production performance of the freshwater fish.