The invention relates to azo compounds containing gem-difluoro methylene and a preparation method of the azo compounds. The structural formula of the azo compounds is shown in the specification, wherein X is O, S and N-Bu; and Ar is shown in the specification, wherein R is an aldehyde group, halogen, ethyl carbonyl, a cyano group, nitro, trifluoromethyl or methyl. According to the azo compounds containing the gem-difluoro methylene and the preparation method of the azo compounds, coupled reaction is conducted between 1,3-benzoxadiazole-2-difluromethyl sulfinic acid sodium and tetrafluoride boronaromatic diazonium salt under promoting of transition metal salt, and the series of azo compounds containing the gem-difluoro methylene are generated; the raw materials are easy to get; operation is easy and convenient; the reaction condition is mild; and the azo compounds have good tolerance on active groups.