The anthocyanins of blackcurrant were isolated and purified by combination of AB-8 macroporous resin and Sephadex LH-20, and the liquid chromatography-mass spectrometry was employed to identified anthocyanins components of blackcurrant. The degradation kinetics of anthocyanins with different purity were analyzed under different pH values and temperatures. Besides, the antioxidant activities were assessed by hydroxyl, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-amino-di(3-ethyl-benzothiazoline sulphonic acid-6) ammonium salt(ABTS) free radical scavenging assays. The results showed that five anthocyanins were identified in terms of delphinidin-3-glucoside,cyanidin-3-rutinoside, petunidin-3-glucoside, paeoniflorin-3,5-dihexoside and malvidin-3-galactoside. The two purified anthocyanins fractions were obtained， which were identified as delphinidin-3-glucoside (A3) and cyanidin-3-rutinoside (A4), respectively. The thermal stability of anthocyanins was strongest at pH 3.0 and temperature 50 ℃. The thermal degradation of anthocyanins with different purity were fitted well to the first-order reaction kinetics, and the correlation coefficients R2 are all above 0.9. Under the same pH value, the degradation rate constant increased, but the half-life and activation energy decreased with the increase of temperature. The IC50 of DPPH free radical scavenging rate of anthocyanins purified by macroporous resin (A1), anthocyanins extracted by ethyl acetate (A2), (A3) and (A4) were 9.45, 8.17, 5.95 and 7.62 mg/L, respectively, and the IC50 of ABTS+ free radical scavenging rate of them were 99.38, 97.21, 78.19 and 85.54 mg/L, respectively. and malvidin-3-galactoside. The two purified anthocyanins fractions were obtained by combination of AB-8 macroporous resin and Sephadex LH-20, which were identified as delphinidin-3-glucoside and cyanidin-3-rutinoside, respectively. The thermal stability of anthocyanins was strongest at pH 3.0 and temperature 50 ℃. The thermal degradation of anthocyanins with different purity were fitted well to the first-order reaction kinetics. Under the same pH value, the degradation rate constant increased, but the half-life and activation energy decreased with the increase of temperature. In vitro antioxidant experiments showed that blackcurrant anthocyanins had significant scavenging abilities of DPPH and ABTS+ free radicals.