The adsorption characteristics and purification process of the polyphenols from Sonchus oleraceus L. by macroreticular resin were investigated. Meanwhile, the chemical composition on crude and pure products of the polyphenols were also analyzed. The static capacity absorption, static capacity desorption, static adsorption isothermal (Langmuir and Freundich), dynamic absorption ratio and dynamic elution ratio of six types of macroreticular resin were studied and compared, in order to find the best one, and the adsorption and desorption performances of the best one were studied in detail. The results showed that the type of NKA-9 resin gave the best effect on separation with the sampling rate 3 BV/h, sampling concentrations of 0.5 mg/mL, the concentration of elution , 50% ethanol in pH 5 with eluting velocity 1 BV/h. The polyphenols of Sonchus oleraceus L. gained under these conditions was 72.38%, and 4.92 times more than that of the original sample. The results of chromatography analysis with HPLC showed that rutin, chlorogenic acid, caffeic acid, apigenin and original catechins were the main components existing in the polyphenols. The content of apigenin were 8.53 mg/g, and 20.16 times more than that of the crude sample after NKA-9 macroporous resin purification.