Plant lectins, particularly those derived from Phaseolus lunatus, Phaseolus vulgaris, and Vicia faba, are of critical importance in the field of medicine due to their potential for blood group identification, as they induce conjugation between cell surface proteins. Therefore, establishing accessible, cost-effective, and efficient blood typing methods is essential for various medical interventions such as transfusions and organ transplants. The objective was to evaluate the hemagglutinating activity of plant lectins on different human erythrocyte types (A, B, AB, O) in order to identify affinity patterns. Erythrocyte agglutination tests were performed on 97 biological samples (human blood) treated with EDTA (ethylenediaminetetraacetic acid), using a pre-experimental, cross-sectional analytical design. The results showed significant differences (p = 0.000), indicating that plant lectins have a different effect between them. This result was corroborated by a Post Hoc analysis, which revealed significant differences (p = 0.000) and (p = 1.000), with the comparison showing no significant differences at (p = 1.000). In conclusion, variations exist in the agglutinating effect of plant lectins, suggesting that while some lectins show evident variations, others may have no significant impact, warranting further investigation. Therefore, it would be appropriate to incorporate these additional factors into the analysis to gain a more comprehensive understanding.