The invention relates to a biological preparation method of 3-amino-4-(2,4,5-trifluorophenyl)
methyl butyrate. According to the biological preparation method, 3-carbonyl-4-(2,4,5-trifluorophenyl)
methyl butyrate is used as a substrate; under the condition that a biocatalyst, a
cofactor, an amino donor and a cosolvent exist, the substrate performs the reaction to generate a target product 3-amino-4-(2,4,5-trifluorophenyl)
methyl butyrate; the biocatalyst is recombination
aminopherase; and the reaction is carried out in water-phase
buffer solution with the pH of 6.0 to 9.0. The biological preparation method realizes that 3-carbonyl-4-(2,4,5-trifluorophenyl)methyl
butyrate is converted into 3-amino-4-(2,4,5-trifluorophenyl)methyl
butyrate by adopting the recombination
aminopherase for the first time; compared with a conventional chemical method, the biological preparation method has low
energy consumption, is simple and convenient to operate, generates a small number of by-products; and moreover, the product has high optical activity.