GA-g-PAA/ST composite hydrogels were prepared by graft copolymerization of gum arabic (GA),acrylic acid (AA),sepiolite clay (ST) under microwave irradiation.The structure and morphology of GA-g-PAA/ST composite hydrogels were characterized by FTIR XRD and SEM.The thermal stability of the hydrogel was analyzed by TG.The swelling behavior and water retention of the hydrogel in different cationic salt solutions were also discussed.The results showed that the graft copolymerization reaction took place between the two groups,and the copolymer intercalated into the interlayer of ST to form a delaminated three-dimensional network composite hydrogel.When the concentration of salt is 20mmol/L,the absorbency of the hydrogel in NaCl、BaCl2、AlCl3 solution is 112、38 and 29g/g,respectively.When the concentration of surfactant solution was 20mmol/L,the absorbency of the hydrogel in SDS solution and CTAB solution was 135 and 105g/g,repectively.After three cycles of NaCl and BaCl2 salt solution,the water absorption ratio of the hydrogel is 80 and 12g/g,indicating that the hydrogel has strong salt responsive property and good reversible behavior in NaCl and BaCl2 salt solution.The hydrogel has good thermal stability and water retetion.