A novel gum arabic-g-poly(2-acrylamido-2-methylpropanesulfonicacid) superabsorbent resin was synthesized by aqueous solution polymerization using microwave irradiation in the presence of potassium persulfate (KPS) as a initiator and N, N-methylene-bis-acrylamide (NMBA) as a crosslinking agent. The effects of the mass ratio of AMPS to GA, crosslinker, initiator, neutralization degree, power and time on the water absorbency of superabsorbent resin were investigated systematically, and the swelling properties of superabsorbent resin were studied. The chemical micstructure of GA-g-PAMPS superabsorbent resin was determined by FTIR. Under the optimum reaction conditions,the water absorbency of superabsorbent resin is 683g/g in the deionized water and 137g/g in normal saline. The water absorbency of the superabsorbent resin decreases with increasing concentration of various external saline solutions, and has the following tendency in different metal ions saline solutions: NaCl>CaCl2> FeCl3,The superabsorbent resin has a high water absorbent rate and a good reswelling capability。