The invention discloses a leather detergent, which consists of 1,500g of turpentine, 1,200g of flaked soap, 500g of gasoline, 800g of silicones, 300g of ammonia water, 200g of vaseline, 300g of setanol, 200g of castor oil, 100g of hexane, 200g of essence, 300g of organic solvent, and 2,000g of deionized water. A preparation method for the leather detergent comprises the following steps of: mixing the turpentine, the flaked soap, the gasoline, the silicones, the ammonia water and the deionized water according to a ratio, and uniformly stirring; adding the vaseline, the setanol, the castor oil and the hexane for mixing, and uniformly stirring; and finally adding the essence and the organic solvent, fully stirring uniformly, and packaging into finished products.