A lectin was isolated from Ulex europaeus seeds by affinity chromatography on affinity adsorbent prepared by copolymerization of acrylamide, N, N 1-methylene bisacrylamide and maleylated hog stomach peptone. The lectin is homogeneous as judged by ultracentrifugation ( s 20,w = 6.4 S), electrophoretic and gel chromatography criteria; it contains 4.2% neutral sugar and 1.4% glucosamine. Its molecular weight is approx. 110 000 and the molecule consists of two non-covalently linked protomers which are formed by two covalently bound basic subunits ( M r = 30 000). The preparation contains three isolectins differing in the strenght of interaction with specific sugars (cellobiose, N-acetyl-D-glucosamine) under the conditions of affinity electrophoresis. The lectin is non-specific with human ABO blood group system, the agglutination is inhibited by partial chitin hydrolysate, hog stomach peptone and high concentration of cellobiose.