Abstract: Extraction and antioxidation of polysaccharides in Chinese honeylocust spine was studied.The polysaccharide content of Chinese honeylocust spine was extracted with ultrasonic assisted technology and determined by phenol-sulfuric acid method using glucose as standard reference at the wavelength of 484 nm.The optimized conditions found by a series single-factor test and L9(34) orthogonal experiment were as follows:extraction temperature was 50 ℃;pH was 7;extraction time was 40 min and ratio of liquid to solid was 30∶1.Extraction yield of polysaccharide in Chinese honeylocust spine found was 1.26%.The antioxidative experiments indicated that removal rates of ·OH,DPPH· and ·O2- found were 88.9%,89.3% and 42.3%,respectively at mass concentration of polysaccharide in Chinese honeylocust spine of 2.5 g·L-1.