Abstract:Anthocyanins from Zi juan tea were exteacted by using acid-containing methanol as solvent and patitioned with ether and chloroform.The extract of anthocyanins was purified by Amberlite XAD-7HP chromatography.The antioxidant and free radical scavenging capacity of anthocyanin extracts were evaluated by DPPH method.The uncertainty of the antioxidant was assessed.The expanded uncertainties were 0.132 2（Trolox mg/kg），which showed that the level of the measurement had the high quality and the data resulted by these methods was worth believing.This study will provide scientific basis for developing and utilizating of Zi juan tea and contribute the depth of processing of food materials and functional application.