Poly(vinyl alcohol)/maleic anhydride/acryloyl thioamide monomer (PVA/MA/ATM) photo-cured nanofiber membranes and pure PVA nanofiber membranes were produced by the electrospinning technique. In situ UV radiation was applied during the electrospinning in order to provide polymerization during the jet flight and promote crosslinking of ATM and MA with PVA. The cross-linking was examined by Fourier transform infrared spectroscopy (FTIR). The morphology of the electrospun nanofibers was characterized by scanning electron microscope (SEM). The surface area of the nanofiber membranes was measured by Brunauer-Emmert-Teller (BET) analysis. Furthermore, their water durability was examined. The water durability test demonstrated that the in situ photo-cured PVA/MA/ATM nanofiber membrane had the lowest average mass loss. The surface areas of PVA/MA/ATM nanofiber membranes were 160-280 m(2) g(-1). The surface area and diameter of PVA/MA/ATM nanofibers decreased with increasing PVA content. The diameter of the obtained nanofibers was less than 100 nm. The results showed that water-insoluble nanofiber membranes with good chemical and thermal resistance were obtained. These nanofiber membranes may be promising candidates for usage in water treatment.