The invention discloses a cattle hide treatment agent and a preparation method thereof and belongs to the chemical field. The treatment agent comprises the following components in parts by weight: 20-30 parts of 128 epoxy resin, 150-200 parts of 3000-molecular-weight polyester polyol 2430, 350-450 parts of butanone I, 100-200 parts of butanone II and 350-450 parts of acetone. The cattle hide treatment agent is prepared by reaction of special combination of 128 epoxy resin, polyester polyol 2430 and butanone in a manner of taking butanone as a reactant. The cattle hide treatment agent is long in service life and high in adhesion, is environmental-friendly and is free of undesirable odor; compared with the similar products, the cattle hide treatment agent is mainly characterized by sealing oil in the cattle hide and preventing the oil from overflowing, so that the adhesion strength is ensured; the cohesion is improved; the cattle hide treatment agent has the property of epoxy resin and is extremely worthy of popularization and implementation.