The invention provides a method for synthesizing beta-fluoro-alpha,beta-unsaturated ketene compounds, which comprises the following steps: converting alpha,beta-unsaturated ketene compounds into corresponding carbonyl oxime ether compounds, mildly implementing sp2 alkenyl hydrocarbon chain direct fluoridation of high-selectivity beta- position in the presence of a palladium catalyst, a fluoridation reagent and additives, and finally, rehydrolyzing oxime ethers under the action of acid to obtain the beta-fluoro-alpha,beta-unsaturated ketene compounds. The fluoridation method has the advantages of mild reaction conditions, high substrate adaptability, high fluoridation selectivity and the like, is simple to operate, and has higher application research value.