Objectives: To assess the influence of the genetically engineered biologic drug etanercept on the quality of life of patients with juvenile idiopathic arthritis (JIA). Methods: The research included 85 children with poly-and oligoarticular variant of the JIA at the age of 5 (2; 17) years. The assessment of the quality of life of patients was carried out by means of the parental version of a special questionnaire CHAQ (Childhood Health Assessment Questionnaire), Health Utilities Index Mark 3 (HUI3) questionnaire. The doctor and parents of the patient also assessed the global activity of the illness by the 100-mm visual analog scale (VAS) before the etanercept prescription and in 1, 6 and 12 months. All patients before the etanercept prescription received immunosuppressive agents. Results: Impressive increase in an average point of the quality of life (the response in 1 month after the therapy beginning) was noted by the attributes of a questionnaire of HUI3 «emotions» — from 0.82 (± 0.18) to 0.90 (± 0.13), p =0.001, «cognitive abilities» — from 0.85 (± 0.17) to 0.91 (± 0.18), p =0.006, and «pain» — from 0.78 (± 0.23) to 0.91 (± 0.1), p < 0.001. In 12 months of the treatment the average point of the quality of life raised also by such attributes as «locomotivity» — from 0.85 (± 0.3) to 0.99 (± 0.06), p < 0.0001, and «fine motor skills» — from 0.9 (± 0.19) to 0.98 (± 0.05), p < 0.001. Conclusions: Treatment with the etanercept provided the improvement of the quality of life of children with the JIA and their families, improvement of physical activity and emotional state of patients.