Abstract: The stem and leaf of wisteria sweet potato was used as experimental materials in this paper, the best process condition of extraction of anthocyanin and the comprehensive utilization of by -products resources were discussed. The result showed that the optimum ethanol concentration, the ratio of solid to liquid, extraction time, and extraction temperature were 95%, 1∶40, 50℃, 24h. In addition, the by-product of extracted anthocyanin also could be used, the yield of leaf protein was 7.32% , the yield of fiber was 13.02% , the content of flavone was 6.07% , a lot of nutrient substance was contained in its side product, which could be transformed into treasure, as to improve the utilization of the stem and leaf.