In this research electrochemical modification of polyvinylchloride based heterogeneous cation exchange membrane was carried out using in situ polymerization of polyacrylicacid and magnetic iron–nickel oxide nanoparticles simultaneously. Spectra analysis confirmed graft polymerization decisively. SEM images illustrated that grafted-PAA/ Fe2NiO4 filled the cracks in membrane by simple gel network entanglement. Membrane water content decreased by grafting PAA and adding more nanoparticles in the modifier solution. Membrane potential, transport number and permselectivityin NaClsolution initially showed a decline then started to improve. Ionic permeability and flux of sodium ions improved initially then showed a decreasing trend. Membrane’s electrical resistance decreased by introducing PAA and nanoparticles on membrane surface.