The invention discloses a preparation method of an environment-friendly leather care agent and belongs to the technical field of leather surface treatment. The present invention extracts Litsea Cubeba with deionized water, passes through water vapor to evaporate effective components, collects Litsea Cubeba essential oil after condensing and refluxing to stand and stratify, and then compound it with castor oil, salicylanilide, etc. to form a bactericidal Fatliquoring agent, reacting isooctyl alcohol polyoxyethylene ether with phosphorus pentoxide to synthesize isooctyl alcohol polyoxyethylene ether phosphate, and finally heating with bactericidal fatliquoring agent, silicone brightener, etc., cooling and discharging after ultrasonic treatment, The environment-friendly leather care agent can be obtained. The leather care agent prepared by the present invention has a good penetration effect on various leather products, can penetrate deep into the leather, play a repairing role, and restore good air permeability and softness to the leather. , waterproof, and the care agent has low toxicity and no irritating smell. After use, it will not cause damage to leather, human body and environment, and has broad application prospects.