Abstract:The present experiment was conducted to optimize extraction process of polysaccharide from Suaeda salsa by ultrasonic microwave synergistic method and studied its antioxidation ativity.The effects of ultrasonic power，solid-liquid ratio，extraction time and temperature on extraction rate of Suaeda salsa polysaccharides were investigated based on single factor test.Then the extraction process of Suaeda salsa polysaccharides was optimized by response surface analysis.The extraction process conditions optimized by response surface methodology were as follow ∶ultrasonic power of 366 W，soild-liquid ratio of 0.51 ∶80 （g/mL），extraction time of 21 min，extraction temperature of 70 ℃.Under the optimum conditions，the polysaccharides extraction rate was （10.714±0.720）%.The scavenging effect of Suaeda salsa polysaccharide on·OH，O2-·and DPPH·were obvious and effective.When the solubility of polysaccharide was 5.1 mg/mL，the clearance rate was 89.2 %，81.9%，79.2%，respectively.The result showed that Suaeda salsa polysaccharide had good oxidative stability and was a good antioxidant.