The red algae, carrageenophytes including Kappaphycus alvarezii, Kappaphycus striatum and Eucheuma denticulatum have been cultivating in Vietnam, not only are as source of carrageenans, but also as source of lectins. the authors previously reported the biochemical properties of the isolated lectins from these algae. In this paper, the authors examined the 20 N-terminal amino acid sequences and the binding specificity with pyridylaminated oligosaccharides of the lectins from two species of K. alvarezii and E. denticulatum. The results showed that lectins KAA-2 from K. alvarezii and EDA-2 from E. denticulatum exclusively bound to high-mannose type Nglycans, but not to other glycans, including complex type and a core pentasaccharide of N-glycans. The binding activity of KAA-2 and EDA-2 was slightly different among high-mannose N-glycans examined, indicating that the lectins have higher affinity for those having the exposed (al-3) Man in the D2 arm. On the other hand, KAA-2 and EDA-2 did not bind to a free oligomannose that is a constituent of the branched oligomannosides, implying that the portion of the core GIcNAc residue(s) of the N-glycans is also essential for binding to the lectin. In the biological activity assay, EDAs, the mixture of lectins from E. denticulatum, inhibited the growth of shrimp pathogenic bacteria, Vibrio alginolyticus, although it did not affect the growth of V. parahaemolyticus and V. harveyi. The growth inhibition of V. alginolyticus with EDAs was not observed in the presence of yeast mannan bearing high mannose N-glycans, suggesting that EDAs caused the activity through binding to a target receptor(s) on the surface of V. alginolyticus. Thus, the cultivated carrageenophytes are a good source oflectin(s) that may be useful as a carbohydrate probe and an antibacterial reagent.