We prospectively studied the serum zinc status and development of HIV infection in HIV infected ex-intravenous drug users (IDUS). It was prospective study of 75 persons (53 HIV infected persons, 22 controls). All patients in this group were observed and examined at baseline and every 3 months. We performed clinical examinations and completed blood counts, chemistry blood examinations, serum zinc level, LCD4 cells count. We found lower serum zinc level in HIV infected patients in comparison with control group. There was no significant difference among serum zinc level in male HIV positive patients in comparison with female HIV positive patients and in HIV infected patients with liver disease and in HIV infected patients without liver disease. In subgroups divided according to the degree of immunity deficiency (according to CDC classification) we do not show characteristic statistical differences in serum zinc level in comparison with control group.