The invention discloses a processing method to concentrate and separate the mother liquor of ainothiazoly loximate by using the membrane separation technology, comprising the following steps: (1) pre-processing the mother liquor of ainothiazoly loximate which is to be treated to remove tiny suspended solids; and (2) under the conditions that the operating pressure is 0.5-4.0 MPa and the temperature is 10-80 DEG C, concentrating and separating the pre-processed mother liquor of ainothiazoly loximate by nanofiltration components to obtain the concentrated solution in which the weight percent ofainothiazoly loximate is above 10%, crystallizing the collected solution; rectifying the percolate to recycle ethanol and discharging or directly discharging the percolate into a sewage treatment station to treat. The invention has the advantages that the mother liquor of ainothiazoly loximate can be effectively concentrated so that not only can the effective constituents of ainothiazoly loximatebe recycled from the mother liquor to ensure the quality of ainothiazoly loximate, but also the indexes of COD, BOD and the like discharged from the mother liquor can be reduced, thus reducing the pollution and energy consumption and having remarkable economic and social benefits. The invention can be widely applied in the occasions to concentrate and recover ainothiazoly loximate.