Preparation method of antibacterial coating

The invention provides a preparation method of an antibacterial coating. The preparation method comprises the following steps: (1) sequentially and respectively adding a silane coupling agent, an adhesive, an antibacterial agent and an organic solvent into a reaction kettle to obtain a polymer, wherein the weight part ratio of the silane coupling agent to the adhesive to the antibacterial agent to the organic solvent is (1-348): (2-250): (3-120): (16-340); (2) dropwise adding 200-980 parts by weight of deionized water or distilled water into the polymer in the step (1), and stirring at the rotating speed of 100-300rpm while dropwise adding to obtain the antibacterial coating; (3) stirring the antibacterial coating obtained in the step (2) at the rotating speed of 20-50rpm for 2 hours, transferring into a sealed container, and standing for more than 12 hours; the preparation method has the beneficial effects that the sprayed coating has a long-acting antibacterial effect and has relatively high alkali resistan