The Lewis blood groups, the secretion of ABH antigens and the frequencies of the related genes were determined in some Israeli Jewish populations of different origins. In total 834 individuals were investigated for ABH antigen secretion and of these, 452 for the Lewis antigens. The frequencies of the le gene in the East European, Central European, North African and Middle Eastern groups were 0.3635, 0.3397, 0.3015 and 0.2293, respectively. The frequencies of the se gene in the same groups were 0.4787, 0.4804, 0.5301 and 0.5468. In a South European and a Yemenite Jewish group, studied for the secretor status only, the obtained se gene frequencies were 0.4879 and 0.4663 respectively. Comparing the four groups studied both for Lewis blood groups and for secretor status, the smallest genetic distance was found between the East and Central European groups, and the greatest, between the East European and Middle Eastern groups.