Abstract: Objective: To develop the optimal extraction technology of polysacchrides from residue of Ginkgo Biloba , and conduct anti-oxidant tests. Methods: Taking the extraction ratio of polysaccharides for evaluation index and detected by phenol-sulfuric acid method, the optimal technology is obtained through single factor experiments. And experiments are taken on reducing activity and scavenging activity against DPPH. Results :The optimal extraction conditions are material-to-liquid ratio of 1:7, extraction time of 2 hours, 2 times, alcohol precipitation concentration of 90%, alcohol precipitation time of 1 hours . The polysaccharides obtained have a rather good reducing activity and scavenging activity against DPPH . Conclusion :The technology is convenient and workable, stable and dependable, which is suitable for industrial manufacture. The polysaccharides obtained have strong anti-oxidant activities.