Modified poly(aspartic acid )/poly(acrylic acid) /carboxymethyl cellulose composite superabsorbent resin was prepared using modified poly (aspartic acid)(KPAsp),acrylic acid (AA) and carboxymethyl cellulose (CMC) as raw materials in an aqueous system. The composition structure, thermal stability and surface morphology of the products were characterized by Fourier-transform infrared spectroscopy(FTIR), thermal gravimetric analysis(TGA) and scanning electron microscopy(SEM).The effects of the amount of CMC and AA on swelling ratio of composite superabsorbent resin were investigated,the results showed that the optimal mass ratio of AA to CMC to modified polysuccinimide (KPSI) was 0.15:3:1,the swelling ratios of prepared composite resin were 830 g/g in distilled water and 130g/g in physiological saline respectively.The salt sensitivity, temperature sensitivity and pH sensitivity of KPAsp / PAA / CMC composite resin with different composition were studied, and swelling properties of resin in artificial blood, artificial urine and different concentrations of ethanol aqueous solution was also studied. The results showed that the salt sensitivity of the composite resin was increased, swelling ratios of resin in different salt solutions were NaCl> FeCl3> CaCl2;The lower critical solution temperature (LCST) of KPAsp/PAA/CMC was 15 ℃ higher than that of KPAsp,the composite resin had the best swelling ratios at pH=5 and pH=9; The maximum swelling ratios of the composite resin were 211 g/g in artificial blood and 142 g/g artificial urine, respectively. The maximum swelling ratios of the composite resin was 295 g / g in the 50% ethanol aqueous solution.