The invention relates to the field of organic synthesizing, discloses a synthesizing method of difluoroalkyl substituted flavonol, isoflavonol and coumarin compounds under simple conditions, and particularly relates to a method using simple flavonol, isoflavonol and coumarin compounds and bromine difluorophosphonate to prepare the difluoroalkyl substituted flavonol, isoflavonol and coumarin compounds in a high-yield manner. The method has the advantages that the flavonol, isoflavonol and coumarin compounds and bromine difluorophosphonate which are extracted by using natural products are used as the raw materials to selectively prepare the difluoroalkyl substituted flavonol, isoflavonol and coumarin compounds in a high-yield manner in the presence of weak alkali which is cheap and easy to obtain; the method is mild in reaction condition, wide in substrate application range, simple to operate, high in reaction efficiency, and the like; the prepared difluoroalkyl substituted flavonol, isoflavonol and coumarin compounds have biological activity such antitumor activity and anti-oxidation activity, are quite important intermediate, can be used for further chemical modification and are promising in application prospect in the field of biological medicine.