Polyvinylchloride(PVC)-mSA/mCS bipolar membrane(BPM) was prepared by the paste method.PVA/sodium alginate(SA) and PVA /chitosan(CS) were cross-linked by inorganic nano-materials and glutaraldehyde(GA),respectively.SEM photographs show that PVA-ZnO-SA/mCS BPM is consists of anion layer and cation layer,the thickness of the BPM is 121 μm,the interface of BPM is 5 μm.Electronic spectrum(EDS) indicates that ZnO well-distributed in cation layer.J-V curve and AC impedances of BPMs were investigated.It can be seen that PVA-ZnO-SA/mCS BPM shows lower working voltage,smaller membrane impedance,and ideal nano-ZnO modification effect.In addition,the dopping nano-ZnO improves the hydrophilic property and mechanical properties of the BPM.Therefore,PVA-ZnO-SA/mCS is an excellent BPM and can be widely used in the green chemistry and environmental management.