The anthocyanins from black soybean peel were extracted with ethanol extraction method. The anthocyanins were purified by macroporous resin. The crude product was obtained after freeze-drying. The anthocyanin fraction was isolated by medium-pressure liquid chromatography and identified by mass spectrometry. The results showed as followes: the total anthocyanin content in the crude product of black bean peel was 26.9%; the purity of cyanidin-3-glucoside in the 2 peaks after separation of black soybean peel crude anthocyanins by medium-pressure liquid chromatography reached 91.46%. The main anthocyanins in the black bean peel were Pelargonidin-3-O-rutinosie, Peonidin-3-O- glucoside, Cyanidin-3-O-glucoside and Vitisin B.