In this work, trials have been made to prepare different graft copolymers by direct irradiation grafting technique and evaluating their reverse osmosis properties. The acrylic acid monomer was grafted onto two improper polymers (low and high-density polyethylene) by means of gamma-ray as a motivator. The optimum conditions of preparation were using acetone as a solvent, monomer concentration 30% (wt/wt), using anhydrous ferric chloride as an inhibitor with optimum concentration 0.1% (wt/wt) and irradiation dose 20 KGy. Mechanical, rheological and thermal properties of the prepared membrane were also investigated. The prepared grafted membranes showed significant results in RO desalination method using underground saline water from Abo Swear, Ismailia, Egypt. Copyright © VBRI Press.