Method for simultaneously preparing dichlorohexafluorocyclopentene isomers

The invention relates to a method for simultaneously preparing dichlorohexafluorocyclopentene isomers. The method comprises the following steps: a raw material perhalocyclopentene or/and perhalocyclopentadiene undergo(es) a liquid phase fluorine-chlorine exchange reaction in the presence of a fluorination reagent and a solvent under a stirring condition to obtain four trichloropentafluorocyclopentene isomers, and one or more of the four trichloropentafluorocyclopentene, adopted as a raw material, undergo(es) a fluorine-chlorine exchange reaction in the presence of the fluorination reagent and the solvent to obtain the dichlorohexafluorocyclopentene isomers. The method has the advantages of easily available raw materials, cheap fluorination reagent, high yield of the isomers, and suitableness for simultaneously preparing perhalocyclopentadiene isomers through a large-scale liquid phase reaction.