Serum zinc, copper, iron, and vitamin A levels were determined in patients with leprosy and healthy controls. Leprosy patients were classified according to the Ridley and Jopling classification and divided into two main groups as follows: tuberculoid, which consisted mainly of borderline tuberculoid patients and lepromatous, which consisted of borderline lepromatous and true lepromatous patients. The lepromatous group was found to have significantly lower serum levels of zinc and iron and elevated levels of copper. Vitamin A levels were also significantly lower in the lepromatous groups than in the tuberculoid group. Furthermore, the true lepromatous vitamin A determinations were significantly lower than those of the borderline lepromatous patients. The mechanism of these alterations in trace elements is probably due to a redistribution of these metals from the blood to various tissues; brought about by the release of leucocyte endogenous mediators by continuing phagocytosis of tissue macrophages in the lepromatous group of patients.