Abstract: Objective:This study was aimed to optimize polysaccharides extraction from Abrus cantoniensis Hance and investigate its antioxidant activity in vitro. Methods:The mathematical model was established by response surface method (RSM) based on the results of single factor experiments, using polysaccharides extraction rate as response value and the ratio of water to material, enzymolysis extraction time duration, cellulase concentration and enzymolysis extraction temperature as experimental factors, which were used to screen optimum polysaccharide extraction conditions from Abrus cantoniensis Hance. Antioxidant activity of polysaccharides was detected by DPPH·and·OH scavenging capacity system. Results:The optimum extraction conditions were as follows:The ratio of water to feedstock was 13:1 mL/g, cellulase enzymolysis extraction time duration was 60 min, the cellulase level was 12.8 mg/mL, enzymolysis extraction temperature was 50℃, the pH value was 5.0. Under the optimal conditions, there was a difference of less than 5% between predicted extraction rate 8.34% and experimental extraction rate 8.15%. The polysaccharide yield was most significantly affected by cellulase concentration, followed by water to material ratio, extraction time duration and extraction temperature. IC₅₀ of Abrus cantoniensis Hance polysaccharide eliminating DPPH·and·OH free radical were 1.591 and 1.926 mg/mL, respectively. Antioxidant activity of sample polysaccharides was weaker than those of vitamin C. Conclusion:The polysaccharide extraction process from Abrus cantoniensis Hance by cellulase enzymolysis approach was obtained, which was convenient and feasible, and the extracted polysaccharides had good antioxidant activity in vitro.