Scoliosis adversely affects the physical and mental health of children and adolescents. The scoliosis deformity develops faster during the period of intensive growth and development, which, in the absence of treatment, can lead to numerous disorders in many body systems, including the immune system. Study of the impact of the reactive response of peripheral blood neutrophils in adolescents (15-17 years old) with and without scoliosis. The reactive response of peripheral blood neutrophils of adolescents in two groups (experimental and control) was evaluated according to the indicators of the peripheral blood neutrophils reactive response rate, the neutrophil-to-lymphocyte ratio (NLR), the neutrophil, leukocyte shift ratio; the neutrophil-to-monocyte ratio: lymphocyte-to-granulocyte ratio, leukocyte to ESR (erythrocyte sedimentation rate) ratio; non-specific reactivity index. Statistical processing of the obtained results involved well-known methods of variable statistics. The peripheral blood neutrophils reactive response rate in boys with scoliosis decreased by 25.0%, while the lymphocyte-to-granulocyte ratio increased by 6.53%, the leukocyte to ESR ratio increased by 33.33%, while the neutrophil-to-monocyte ratio increased by 1.37% compared to the control group. The reactive response of peripheral blood neutrophils in adolescent girls with scoliosis is higher according to the neutrophil reactive response rate and the neutrophil shift rate by 25.0%, according to the lymphocyte-to-granulocyte ratio —by 16.97%, and lower according to the neutrophil-to-monocyte ratio by 13.10%, according to by the neutrophil-to-lymphocyte ratio — by 16.75%, according to the leukocyte shift ratio — by 16.46%, according to the leukocyte to ESR ratio — by 4.76%. It was found that the reactive response of peripheral blood neutrophils in adolescents with scoliosis, depends on gender and individual specifics of the reactive response: boys were found to have an increased reactive response of peripheral blood neutrophils was found compared to the reactive response of neutrophil granulocytes in girls. It is appropriate to continue research in this direction with the involvement of a larger category of respondents in a wider age group. Keywords: adolescents, scoliosis, cellular reactivity, neutrophils, granulocytes.