Abstract: Color protecting processing in the pretreatment of burdock was studied to enhance polyphenols extraction. Extraction technological parameters including extraction time,ethanol concentration,extraction temperature,and solid-liquid ratio were optimized with orthogonal experiment.The results showed that VCwas the suitable color protection agent.At the concentration of 0.75%,the pretreatment of VCcould improve the extraction rate of burdock polyphenol.The result also showed that the optimal extraction condition were as following: solid-liquid ratio of 1∶ 9,extraction temperature of 75 ℃,extraction time of 65 min,ethanol solvent concentration of 65%.Under the optimal conditions,the extraction rate of polyphenols reached 7.12%.