This study investigates the effect of surface modification by deposition of electrospun fibers on properties and performance of three different microporous polypropylene/polyethylene (PP/PE) commercial nonwoven membrane supports (Novatexx 2430, 2465 and 2473). Polyamide (nylon 6) nanofiber webs with a small number of defects and fibers of about 100 nanometer diameter were successfully deposited onto a surface of the selected membrane supports. FESEM was used to examine microstructure and morphology of the unmodified substrates and the prepared composite two-layer membranes. DSC was applied to investigate thermal stability and FT-IR analysis to confirm the chemical composition of the studied membranes. Saline water permeability tests of the prepared two-layer composite membranes were carried out. The largest pressure difference was measured for PA nanofiber/Novatexx 2430 sample, which was ascribed to a denser net structure of the membrane support and possibly to the newly formed layer of dissolved salts on the membrane surface.