Poly（m-phenylene isophthalamide）（PMIA） flat sheet ultrafiltration membrane based on the support of nonwoven fabric were fabricated under the condition of using DMAc as solvent

lithium chloride and PEG400 as mixed additives

and the influence of PEG400 and Li Cl content on the structure and performance of the membranes were investigated. Effect of mixed additives content on the viscosity of the casting solution

the morphology and the characteristics of the resulted membranes were investigated in detail. The results showed that when the ratio of Li Cl to PEG400 increased from 5 ∶0 to 5∶2

the membrane surface morphology mainly showed that the membrane pores became smaller and the membrane surface became more compact. The lowest contact angle of the prepared membrane water was 46.7°

indicating good hydrophilicity.The results of ultrafiltration experiment showed that the PMIA flat sheet ultrafiltration membrane prepared under the condition of 5∶2 mass fraction ratio between Li Cl and PEG400 had the pure water flux of 2 692 L/（m2·h·MPa） and the BSA retention rate of 96.5%. The flux of PMIA membrane remained stable after 6 h ultrafiltration operation of 100 mg/L HA solution

and the study showed that the membrane had good anti-pollution performance.