By Sepharose 4B-thyroglobulin affinity column chromatography a lectin was purified from Bellamya purificata. It showed a single band on alkaline PAGE. This lectin (BPL) agglutinated red blood cells of rabbit,duck and pig,but not of human blood types or formalin and/or glutaraldehyde-fixed rabbit erythrocytes. Its agglutination activity could be inhibited by 1.0mol/L lactose or galactose as well as 60g/L thyroglobulin, but not by alkaline borate buffer.BPL was temperature-sensitive,while showed a broad optical pH range (pH4.56-9.96).