Background. The consequence of iodine deficiency is a decrease in the secretion of thyroid hormones, which adversely affects the immune system with the development of somatic and predisposition to frequent respiratory diseases. The purpose was to investigate the iodine supply of the body of children with recurrent respiratory infections (RRI) by studying the organification and inorganic fractions of iodine in the serum and excretion of iodine in the urine. Materials and methods. The study was conducted by simple sampling, taking into account the characteristics of the clinic course of respiratory disease. Clinical and laboratory and instrumental examination was performed in 60 children aged 3 to 11 years with a diagnosis of RRI. The concentration of iodine in urine, the level of inorganic and organification iodine in the blood were studied. Results. The clinical picture presented with the symptoms of intoxication, fever, and catarrhal symptoms typical of RRI. In children with severe RRI experienced a clear decrease in the iodine level to 57.34 μg/l (p < 0.05) and a decline in the blood content of total iodine and iodine organification by 31.12 and 39.11 % (p < 0.001), respectively. The concentration of inorganic iodine was significantly higher (p < 0.001). Such results indicate a “wrong” subcellular distribution of iodine into fractions in the inflammatory process caused by RRI. The children with detected iodine deficiency demonstrated a more severe course of RRI. There was a moderately negative relationship between the levels of organification and inorganic iodine (r = –0.515; p < 0.05) and a direct relationship between the blood concentrations of total and organification iodine (r = 0.899; p < 0.05). Conclusions. The course of RRI in patients with iodine deficiency is characterized by an increase in the level of inorganic iodine, a decrease in organification iodine and total iodine, the deepening of these changes correlates with the severity of the respiratory disease.