The invention discloses a deuterated compound synthesis method, which comprises: carrying out a mixing reaction on a halogenated compound represented by a formula (I), a sulfide represented by a formula (II), a promoter, an alkali and a deuteration solvent to obtain a reduced deuterated product represented by a formula (III), wherein the reaction equation of the reaction is defined in the specification, R<1>, R<2>, R<3> and R<4> respectively are at least one selected from alkyl, aryl, acyl, hydrogen atom and deuterium atom, and X is at least one selected from iodine, bromine and chlorine. According to the present invention, the deuteration marking of the compound is efficiently achieved by using the common heavy water and the deuterated alcohol as the deuterium source through the simple reduction reaction, such that the use of expensive, toxic, flammable and explosive deuterium source reagents is not required compared with the prior art. The formulas I, II and III are defined in the specification.