The invention discloses a preparation method for an enkephalinase inhibitor intermediate. According to the preparation method, a target compound with a formula I as described in the specification is prepared by using a compound as shown in a formula IV which is described in the specification as an initial material through a reaction with few steps, wherein the compound with the formula I can be used for preparation of an enkephalinase inhibitor drug namely Sacubtril. In the formula I and the formula IV, R is selected from the group consisting of H, methyl, ethyl or other lower alkyl.