The invention discloses a production method of walnut oil and the produced walnut oil. Annual wild Juglans sigillata Dode is selected, rotten wild Juglans sigillata Dode is removed, and the surface of the wild Juglans sigillata Dode is cleaned and sterilized; the wild Juglans sigillata Dode is dried, cooled and broken by a breaker, and hull and walnut kernels are separated; the walnut kernels are placed in an alkaline liquid and peeled for 8-30 min, fished out, cleaned with clear water and dried at the temperature lower than or equal to 50 DEG C until the water content is smaller than or equal to 3%; the walnut kernels are smashed and fed into a hydraulic presser, and crude oil and oil dreg are obtained through solid-liquid separation; the crude oil is subjected to hydration, deacidification, washing, discoloration, filtration, deodorization and filtration, and the finished product, namely, refined walnut oil, is obtained. The acidity of the produced walnut oil is smaller than or equal to 0.5, the wild walnut oil tastes good, pure original fruit aroma of the wild walnut oil is kept, no rancidity is produced, freshness is kept, saturated fatty acid, linolenic acid and linoleic acid are increased, the walnut oil is difficult to oxidize, nutrition is locked and the like. The preparation process is simple, easy to operate, low in production cost, high in oil yield and suitable for industrial production.