Method for producing propionic acid derivative

An object of the present invention is to provide a method for producing a propionic acid derivative with high productivity. The object can be achieved by a method for producing a compound represented by formula (1):wherein R1 is a halogen atom or the like, R2 and R3 are each independently a hydrogen atom, a halogen atom, or an organic group, X is an oxygen atom or a sulfur atom, R4 and R5 are each independently a hydrogen atom, a halogen atom, or a hydrocarbon group optionally having one or more substituents, R6 is a hydrocarbon group optionally having one or more substituents; the method comprising step A of reacting a compound represented by formula (2):with a compound represented by formula (3):M(R1)n, wherein M is a cation, n is an integer corresponding to the valence of M, and a compound represented by formula (4):R6-X-H; andstep B of separating, by filtration, the compound represented by formula (5): MFn from the mixture obtained by the above reaction.