Abstract: Using enzymatic ultrasonic assisted that investigated for extraction of polysaccharide from Solanum melongena sepa, and their antioxidant activity were determined. The Solanum melongena sepal were hydrolyzed in pH5, 1% cellulase, reaction temperature 50℃ for a hydrolysis duration of 30min. The extracting condition was optimized using response surface analysis. The antioxidant properties of polysaccharide were studied by scavenging of hydroxyl free radical, superoxide anion free radical and reducing power. Results showed that optimal extraction conditions were determined to be 1∶36 (g/mL) , 22min and 68℃. Under these conditions, the extraction rate of polysaccharides was 5.49%. The polysaccharides had high abilities to scavenge hydroxyl and superoxide anion free radicals and excellent reducing power. The corresponding IC50 values against hydroxyl and superoxide anion free radicals were 0.12mg/mL and 0.22mg/mL, however, had weaker antioxidant activity than VC.