Children with attention deficit syndrome with hyperactivity (ADSH) are characterised by attention and motor deficiencies and obvious immune disorders, which manifest as recurrent acute viral respiratory tract infections and changes in immunological parameters. It was established that the structure of deviations in the spectrum of elements in children with ADSH has characteristic features. The atomic emission analysis of cerebrolysin detected an advantageous combination of trace elements with neuroactive and antioxidant properties. The effect of cerebrolysin on immunological parameters was studied in vitro and in vivo. Cerebrolysin was administered in a dose of 1 ml per 10 kg of weight intramuscularly during 1 month. The administration of cerebrolysin resulted in a simultaneous normalization of neurological and immune disorders and in a reduction in the illness rate. In in vitro experiments cerebrolysin enhanced the expression of activation markers (HLA DR, CD25) by CD45(+)CD14(-) lymphocytes, particularly by CD4(+) cells. In vivo it led to the normalization of the numbers of CD4(+), CD19(+), CD16(+) and CD56(+) cells and of the level of serum IgG and IgA. Cerebrolysin normalized the expression of HLA DR molecules on the surface of CD8(+) cells and increased the amount of CD11b(+) lymphocytes. At the same time, it did not affect the level of CD95 molecule expression.