The invention discloses a cross-linked polyquaternary ammonium salt type antibiosis monomer, a preparation method of the cross-linked polyquaternary ammonium salt type antibiosis monomer and application of the cross-linked polyquaternary ammonium salt type antibiosis monomer in dentistry repairing materials. In the preparation method, monomer bonds are connected to a dentistry resin-based material, so as to endow antibiosis property to the resin-based material. The structure general formula of the cross-linked polyquaternary ammonium salt type antibiosis monomer is shown in the specification. The preparation method comprises the following steps: 1, adding a solvent in tertiary amine substance, and adding halohydrocarbon substance for reflux reaction so as to obtain a product A, adding acyl chloride for reflux reaction by using toluene, benzene, dichloromethane or tetrahydrofuran so as to obtain quaternary ammonium salt B, and purifying the quaternary ammonium salt B; and 2, adding the acyl chloride and tertiary amine substancem by using the toluene, benzene, dichloromethane or tetrahydrofuran as the solvent, adding triethylamine as auxiliary, reacting to obtain the tertiary amine containing C=C, the tertiary amine takes acetone, metjylene dichloride and acetonitrile as the solvents, adding the halohydrocarbon for reflux reaction, and then purifying the quaternary ammonium salt monomer. In the invention, reaction steps are simple, the purity of the monomer is high, and the monomer has better compatibility and higher safety as compared with the common dentistry repairing resin monomer.