Abstract: Using water as extraction medium, the extraction rate of buddleja yellow pigment with the ethanol-ammonium sulphate aqueous two-phase system, acetone-ammonium sulphate aqueous two-phase system and conventional process have been studied. The results showed that the maximum extraction rate was 24%(ammonium sulphate aqueous two-phase system), 20%(acetone-ammonium sulphate aqueous two-phase system) and 18% (conventional process). The two-phase system of the ethanol-ammonium sulphate aqueous was suitable for industrial production of Buddleja yellow pigment with simple operation, high extraction rate, low cost and low toxicity.