Examined were 134 children with acute hematogenous osteomyelitis. It was established, that the different outcomes of acute hematogenous osteomyelitis were conditioned by the different in quality variants of the course of the disease with originality of immunologic reactions. In transition of acute hematogenous osteomyelitis to the chronic form at the period of stabilization of acute inflammation in patients, the number of T- and B-lymphocytes, the index of completed phagocytosis remains significantly decreased, and the lysozyme and IgG content of the blood serum--significantly increased.