Abstract: Disclosed is a method of preparing glufosinate, and specifically a method of preparing glufosinate represented by formula (1) or its salt or enantiomer, or a mixture of its enantiomers in any ratio, comprising a step of hydrolyzing a compound of formula (III) to generate a compound of formula (1). Due to a distinctive reaction mechanism adopted in the method of the present disclosure, a halogenated hydrocarbon by-product in the Michaelis-Arbuzov reaction can be avoided and thus the destructive impact of the halogenated hydrocarbon by-product on ozone in the aerosphere can be prevented. Accordingly, the equipment and engineering investments required for the separation, purification, and collection of the foregoing by-product are eliminated, and the potential environmental and safety hazards brought by the foregoing by-product are also avoided.