The invention discloses a preparation method of an untreated fluorine-containing material adhesive, which aims at solving the problem of lower shear strength and stripping strength when the existing adhesive is used for adhesion of an untreated fluorine-containing material. The preparation method comprises the following steps of enabling hydroxy-terminated fluororubber and isocyanatoethyl methacrylate to react under the catalyzing action of dibutyltin dilaurate, so as to form a fluororubber macromonomer; polymerizing with free radicals of acrylic ester, and forming a grafting polymer, so as to obtain the untreated fluorine-containing material adhesive. The preparation method has the advantages that by adopting the fluororubber macromonomer, and introducing a large amount of fluorine-containing groups, the surface energy of an acrylate adhesive is effectively decreased, and the wetting property and adhering strength of the adhesive are greatly improved; the prepared adhesive is used as a special adhesive, and is applied to adhesion of inert materials, such as polytetrafluoroethylene and fluororubber; the shear strength is high, and the stripping strength is high.