Abstract: A novel superabsorbent resin was prepared by graft copolymerization of acrylic acid (AA) onto xanthan gum（XG）with N,N′-methylene diacrylamide as a corsslinking agent initiated with potassium persulfate. The influence of reaction conditions on the absorbency was discussed. The graft copolymers were characterized by means of Fourier-transform infrared spectroscopy（FT-IR）, X-ray diffraction（XRD）, and polarizing microscope (PM). The best conditions for the grafting reaction were found to be that the mass ratio of AA to XG is 6:1, the mass ratio of initiator and crosslinking reagent to xanthan gum is 0.01 and 0.003 respectively, the reaction temperature is 60℃ and the reaction time is 4h. The graft copolymer synthesized with the optimized reaction condition can absorb 854 g/g distilled water and 156 g/g normal saline.