The invention relates to a preparation method of an 
aryl propionic 
acid derivative, comprising the following step of: making a compound expressed by a formula II react according to the following 
route so as to prepare the 
aryl propionic 
acid derivative expressed by a formula I, wherein R1, R2, R3, R4 and R5 independently express 
hydrogen, 
alkyl with 1-4 carbon atoms, alkoxy with 1-4 carbon atoms, 
halogen, trihalogenated methyl and 
nitryl; R7 and R8 independently express an ester group and a cyano group; R6 expresses carboxyl or a cyano group; X expresses 
fluorine, 
chlorine, 
bromine or 
iodine; when R7 and R8 both express the ester group or the cyano group, R6 expresses the carboxyl; and when R7 expresses the ester group and R8 expresses the cyano group, R6 expresses the cyano group. The preparation method of the 
aryl propionic 
acid derivative has the advantages that raw materials are easy to obtain and low in price, oxidation and reduction reaction are not needed, the 
route is simple, the reaction condition is moderate, the production 
equipment requirement is low, a small quantity of the three wastes is discharged and industrialized production can be realized easily, thereby the preparation method can be widely used for synthesizing medicaments, daily chemicals, and the like.