Abstract: The lowcost superabsorbent hydrogel for agriculture and forestry was manufactured by taking the pulverized Eupatorium adenophorum as raw material that was degreased by benzeneethanol mixture. The results showed that the hydrogel with optimal absorbency was obtained under the conditions that the weight ratio of AA/AM graft copolymerization to dry pulverized raw material as 11∶1, the neutralization degree of AA as 45%, the weight ratio of initiator to raw material as 0015∶1.000, the weight ratio of crosslinker to two monomers as 0004∶1.000, the reaction was taken place at 60 ℃ for 5 h. The maximum saturated swelling degree of the hydrogel was 931 g/g in deionized water and 337 g/g in 09% NaCl solution. The evidence of graft copolymerization was determined by using FT-IR spectroscopy, and the surface morphology of the PAA/PAM hydrogel product was characterized by SEM.