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Super absorbent resin was prepared by graft copolymerization of hydroxypropyl methylcellulose (HPMC) with acrylic acid as graft copolymer, ammonium persulfatesodium bisulfite as initiator and polyethylene glycol diacrylate as crosslinker under microwave radiation. The absorbent ratio, absorbent rate and crosslinking rate of super absorbent resin were studied. The water retention properties and IR spectra, thermogravimetric and apparent morphology were characterized. The results showed that the optimum preparation methods were as follows：the mass ratio of HPMC to acrylic acid was 1/7, the neutralization degree was 65%, the mass ratio of initiator to acrylic acid was 1%, the mass ratio of crosslinking agent to acrylic acid was 0.4%, and the reaction time was 4min and 30s. Under the optimum preparation conditions, the water absorption ratio of HPMC super absorbent resin could reach 497.13g/g and the salt absorption ratio was 61.70g/g. This hydroxypropyl methyl cellulose based super absorbent resin could absorb liquid to reach the state of preservation in 30min quickly. The super absorbent resin could retain water for more than 48h at 35℃, 6h at 55℃ and 5h at 75℃. After six times of reuse, the water absorption rate of the super absorbent resin could still reach 69.7% of the initial water absorption rate, and the salt absorption rate could still reach 44.2% of the initial salt absorption rate. The super absorbent resin had good reusability. Thermogravimetric analysis showed that the super absorbent resin had good stability at 330℃. The hydroxypropyl methyl cellulose based super absorbent resin had good water absorption, salt resistance, high water retention rate and excellent reusability.