The invention relates to a processing method of antioxidant nitraria concentrated juice, comprising the following steps of: taking nitraria fruit as raw material, sorting, cleaning, juicing, grinding by a colloid mill and homogenizing by a high-pressure homogenizer, then removing impurities by using a microfiltration membrane, clearing by using the microfiltration membrane, and finally concentrating by a nanofiltration membrane and a reverse osmosis membrane to obtain the antioxidant nitraria concentrated juice. In the processing method, the colloid mill and high-pressure homogenizing and breaking technologies and a membrane separation technology are adopted, thus the production cost and energy consumption of the production process can be effectively reduced, the production cycle is shortened, and the loss of nutrient components and antioxidant active components in the production process is reduced. Simultaneously, the antioxidant nitraria concentrated juice obtained by adopting the invention has the advantages of higher antioxidant activity, good taste and sense, homogeneous property and stable performance.