A hierarchical chitosan/polyvinyl alcohol/polyethylene glycol/nonwoven fabric (CS/PVA/PEG/NWF) micro/nanofiber composite membrane (CM) was prepared via electrospinning as a potential wound dressing. The polyester/viscose NWF acting as a substrate to receive the nanofiber layer was modified by alkali deweighting. Meanwhile, PEG with various additive amount was used to afford morphological regulation and control. As a result, the NWF modified with 7.5% NaOH solution exhibited a good hydrophilia and a superior dimensional stability based on smaller elongation at break and higher peel strength. In addition, the morphology of the nanofiber layer was closely related to PEG content. CS/PVA/PEG nanofiber with smaller diameter was spun when PEG content reached to 3.0%. Accordingly, the micro/nanofiber CM showed an opportune water absorption and good air permeability. Furthermore, neither hemolysis nor cytotoxicity phenomena appeared for the resultant CM, since the hemolysis rate and the cell viability were less than 5% and more than 70%, respectively.