In recent years, evidence was brought of the zinc ion (Zn++) interference in the mechanism of certain processes occurring at molecular level, i.e., the protein synthesis, the activity of some enzymatic complexes, the regulation of transmembranal transport or the processes of immune regulation. The present paper investigates the variations of the immunoglobulin classes in patients with bronchial asthma, particularly the relationship between IgD levels and those of the zinc ion in the blood serum.