Lectins are capable of cell agglutination by interacting with the cell surface exposed glycans. Lectins that agglutinate erythrocytes are called hemagglutinin. These compounds occur in various organisms including plants. In this study, twenty edible vegetables were subjected to screen for haemagglutination and lectin activity. Lectin activity was assessed by measuring the inhibition ability of haemagglutination by different sugars. PBS (Phosphate Buffer Saline) treated homogenate was tested for haemagglutination against erythrocytes suspension, and inhibition of agglutination was determined by serially diluted sugar solution. The results of this study demonstrated that one homogenate among the homogenates of 20 vegetables was found to be capable of human erythrocyte agglutination. The Ipomoea aquatica homogenate shown positive haemagglutination reaction against red blood cells (RBCs) with HA titer value of 4 HA-U/25uL, and four out of seven sugars were able to inhibit RBCs agglutination. Among the four sugars, two are potent inhibitors of agglutination. The neutralization of haemagglutination by four monosaccharides provides a suggestion that the lectin present in I. aquatica may be multivalent carbohydrate binding hemagglutinin. This is the first report to identify that Ipomoea aquatica contains lectin protein which is a polyvalent sugar binding lectin and specific for glucose, galactose, mannose and N-Acetyl-D-Glucosamine.