In order to solve the contradiction between high filtration efficiency and high airflow resistance of nanofiber membrane air filtration materials, PA6/PEO composite fiber membranes were prepared by solution jet spinning method, and the fiber diameter was changed by adjusting the molecular weight of PEO, the dual-scale layered structure was constructed by using double sprinklers to achieve high efficiency and low resistance filtration performance. The research found that increasing the molecular weight of PEO leads to an increase in fiber diameter and an improvement in porosity. The dual-scale layered fiber membrane prepared by the dual-nozzle spinning technology, through the synergistic effect of nanofibers (320 nm) and microfibers (1.6 μm), forms a fiber membrane filter material with a fluffy interlaced three-dimensional structure, and the filtration efficiency of this material reaches over 99.5%.