The arrangement of vascular tissues differs in the root and shoots in angiosperms. The root has a solid triarch or tetrarch exarch xylem whereas the stems possess endarch xylem made of individual vascular bundles arranged in a ring form. A continuous flow of water and minerals is not disrupted in spite of this difference in the arrangement of xylem tissue in the two organs. This happens because of a transition region extending from the upper portion of the root, ending in either the hypocotyl or epicotyl where a gradual alteration in the arrangement of the xylem tissue occurs. The aim of the study was to investigate the extent of transition region and the structural anatomy of xylem in the transition region of three tropical legume species viz. Vigna radiata, V. unguiculata (red variety) and Cicer arietinum. Sequential transverse sections from the base of the root, hypocotyl and epicotyl were obtained from five day old seedlings of the three selected legumes, stained with safranin and viewed under the light microscope. Sections were digitally photographed. In all the three species studied, the transition region commenced a few millimeters below the soil surface. In Vigna radiata and Vigna unguiculata it ended in the hypocotyl region above the soil surface whereas in Cicer arietinum it ended in the epicotyl region. The beginning of transition region showed appearance of a pith in the center of the xylem core. Gradual widening of pith resulted in separation of xylem tissue. This was followed by reorientation of exarch to endarch xylem. A variation in the structural anatomy of xylem among the three species was also observed in the length of transition region and structural anatomy of xylem.