The invention relates to a rodent repellent, especially to a biological compound master batch of a rodent repellent. The nanometer microcapsule biological compound master batch of the rodent repellent comprises 1.5 to 2.0% of capsaicin, 1.0 to 1.5% of cinnamamide, 1.5 to 2.5% of concentrated aqueous extract of wild ginger, 0.8 to 1.2% of concentrated organic solvent extract of digitalis, 0.7 to 1.2% of actidione, 0.5 to 1.0% of an embedding capsule wall material and 0.1 to 0.3% of an antiseptic, with the balance being water. The master batch tastes pungent and gives off offensive odor when chewed; meanwhile, the master batch simulates the flavor of urine of predators and has no toxicity when eaten by animals or people; every component has different action mechanisms and cooperated with each other, and the master batch has long-lasting rodent-repelling effect; and the master batch has the advantages of usage of local materials, low cost, convenience in preparation and usage, no pollution to the environment, safety to people and poultry and good rodent-repelling effect.