Abstract: In this paper，the processes of extraction，separation and purification of Phaseolus vulgaris agglutinin（PHA）from the common bean "Bean Saint esprit a oeil rouge" fresh pods were optimized. The effects of extracting agent，material-liquid ratio，pH and extracting time on PHA were studied，and the combined method of ammonium sulfate precipitation， DEAE- 52 anion exchange chromatography and Superdex-200 gel filtration chromatography for extracting，isolating and purifing the PHA from fresh pods of common bean has been established. The main results were as follow：1）The optimized technical parameters for common bean extraction process were material-liquid ratio 1∶25，pH 6-8，extracting time 8 h，PBS as extracting agent；2）The high purity PHA was obtained with ammonium sulfate precipitation，dialysis，DEAE-52 anion exchange chromatography，concentrated by ultrafiltration and Superdex-200 gel filtration chromatography. The obtained PHA shows one band with electrophoresis test and has blood clotting activity.

Key words: common bean, lectin, separation and purification, hemagglutination activity