The zinc, an important enzymatic cofactor, is involved in many metabolic processes. Its deficiency might be due either to malabsorption or to excessive utilization. In the medical literature of the latest 10 years, zinc was considered to play a part in the immune processes. The authors of the present paper intend to study the zinc and immunoglobulin levels in various diseases, i.e., chronic progressive hepatitis, liver cirrhosis (LC), dermatitis, bronchial asthma. This preliminary investigation was carried out in 30 patients with LC in whom serum zinc values were assayed by atomic absorption spectrophotometry and the immunoglobulin levels were determined using the Mancini type simple radial immunodiffusion technique. All these patients presented considerable decrease of serum zinc concentration, the values ranging between 3.06 and 7.65 mumol/l as compared with 19.8 +/- 1.5 mumol/l in the controls, alongside with the increase of immunoglobulins G and M. In the patients treated with Zincum metallicum CH5 it was observed after about 30 days of treatment that the clinical state was considerably improved and IgG and IgM as well as serum zinc had resumed their normal values. This treatment should not be interrupted since in LC, without permanent additional supply, the serum zinc returns rapidly to the initial deficit or even lower.