The invention discloses a primer promoting agent for bonding of an inert material and a preparation method thereof. The primer promoting agent is prepared from the following components in parts by weight: 100 parts of fluorine rubber, 0.5-5 parts of initiators, 0.5-2 parts of an acrylic ester monomer, 0.1-0.5 part of a fluorine-containing monomer, 100-500 parts of a solvent and 0.005-0.01 part of a crosslinking agent. The preparation method of the primer promoting agent comprises the following steps: weighing components in a weight ratio; dissolving the fluorine rubber into a first part of the solvent, adding the obtained solution into a reactor, heating, dropwise adding a first initiator, and stirring for 1-3 hours; dropwise adding the mixed solution of a second initiator, a second part of the solvent, the acrylic ester monomer and the fluorine-containing monomer, carrying out reaction for 3-7 hours, stopping stirring, cooling to room temperature, discharging the product of reaction, and mixing the product of reaction with the crosslinking agent. The primer promoting agent disclosed by the invention can not cause damage to a substrate and hurt a human body, is well compatible with the inert material and the acrylic ester adhesive and is capable of improving the bonding strength of the inert material greatly.