The invention discloses a preparation method of a mower rubber fitting. The preparation method comprises S1: calcining kaolin and adding the calcined kaolin into dimethyl silicone oil to obtain modified kaolin, S2: adding raw nitrile rubber, raw butadiene rubber, polyethylene glycol and liquid paraffin into a plasticator, carrying out plastication, adding chlorothalonil, 8-hydroxyquinoline, a vulcanizing agent, a vulcanizing aid and a waterproofing agent into the plastic, carrying out mixing, and orderly dispersing carbon black, far Infrared ceramic powder, modified kaolin and carbon fibers to obtain rubber, and S3, adding the rubber into a calendar, carrying out calending and cooling molding, feeding the molded plastic into a vulcanization bed, carrying out two-step vulcanization, wherein in the first vulcanization, a programed heating method is adopted, and carrying out cutting to obtain a mower rubber fitting finished product. The preparation method is easy to operate, has good reproducibility and is used for industrial production. The rubber fitting has excellent water resistance and abrasion resistance and has a high antibacterial rate.