A facile microporous polypropylene membrane (MPPM) surface modification method was developed with controllable grafting density and distribution of amino groups in this paper. Firstly, polymethyl acrylate (PMA) was grafted on the MPPM surface via UV graft polymerization. Then, the grafted membrane was alternately performed the amidation condensation and Michael addition reaction with ethylenediamine and methyl acrylate as the raw reactants for several times. The aminated membranes were characterized by Fourier transform infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS) and environmental scanning electron microscopy (ESEM). The aminated membranes show greatly enhanced surface hydrophilicity and can adsorb water up to 1311.29±97.56 μg/cm2, which is 145 times as much as that of the origin membrane. Furthermore, the aminated membranes have satisfactory performance for water flux and metal ions permeability.