Galectins are beta-galactoside binding mammalian lectins and they share homologous carbohydrate recognition domains. To date, 11 members of galectin family have been cloned and identified. They have been shown to play roles in diverse biological events, such as embryogenesis, oncogenesis, adhesion and proliferation of the cells, receptor for advanced glycation end products, mRNA splicing, bacterial colonization, apoptosis, and in the modulation of the immune response. The mechanisms by which galectins exert these diverse effects remain largely unknown. However, the elucidation of multi-functional proteins belong to galectin family are going to open new fields in clinical science including diagnosis and therapy of autoimmune disorders, cancers, and vascular complications in diabetes and hypertension.