Abstract: To study the inhibitory action of anthocyanins from black soybean seed coat (ABSC) to subgroup A avian leukosis virus (ALV-A) in vitro.ABSC powder was chosen as the raw material and its anthocyanins structure was identified by HPLC-MS.Then in vitro, MTT assay and cell morphological changes were used to observe the cytotoxic effect of ABSC on monolayer DF-1 cells, and cell model was used to research ABSC's prevention and treatment roles in the ALV-A-infected different phase.The result showed that the extract of black soybean seed coat contained four major anthocyanins, the one of the main component was cyanidin-3-glucoside.When mass concentration of ABSC was less than 20μg/mL, DF-1 cells was well-grown without the cell toxicity.Introduced ALV-A to DF-1, ABSC could restrain the proliferation of ALV-A under the 20μg/mL, and inhibition effect was dose-response in the security concentration range.In summary, anthocyanins from black soybean seed coat of 12μg/mL had significantly inhibitory effect for DF-1 cell induced by ALV-A.