Abstract:Lectin was extracted from leaves of Aloe vera L. var. chinensis (Haw.) Berger in a dilute NaCI solution. After centrifugation, the collected supernatant was dialysed. Pure lectin of Aloe (ACL) was isolated by N-acetylglucosandne-Sepharose 4B affinity chromatography and purified by Sephadex G-100 gel filtration chromatography. The apparent molecular weight of ACL was 35 kD. It consisted of two subunits, 15 kD and 20 kD. ACL could agglutinate rabbit erythrocytes and the human erythrocytes with groups A and O specifically, except those with groups B and AB．The activity of ACL was inhibited by D-mannose and N-acetylglucosamine．Neutral sugar content in ACL was 4.8％.