The invention relates to a leather preparation method. The method comprises the following steps: S101, dissolving graphene in an acid solution; and heating for 3-5h under the temperature of 110-130 DEG C; S102, adding a polyethylene acrylate and tourmaline powder to the product obtained in S101; uniformly stirring, and regulating the pH of the product to be 5.8-6.3; S103, adding polyurethane resin and polyvinyl alcohol to the product obtained in S102; uniformly stirring; S104, coating a base leather with the product obtained in S103, so as to obtain the leather. According to the method, the graphene is used as the additive to be applied to the leather preparation process, so that the obtained leather product, in particular a leather bad mat, is outstanding in abrasion and scratching resisting functions, antistatic function, wave absorbing function, bacteria resisting function, mould preventing performance, UV ageing resisting performance, flame resisting and smoke inhibiting performance, electromagnetic shielding function, infrared healthcare function and other function. Therefore, the level of the leather can be comprehensively increased; the comfort, the durability, the mould resistance and the bacteria resistance of national cattlehide bed mats can be improved.