Objective Observe the cIinical effects and features of tumor necrosis factor antagonists (Etanercept) in treatment of systemic onset juvenile idiopathic arthritis (So-JIA),to provide the basis evidence of treatment programs for the So-JIA children.Methods Tumor necrosis factor antagonists were used in treatment of 30 children with refractory systemic onset juvenile idiopathic arthritis,carry out the following evaluation after treatment for 1 month,3months,6months:①The dosage of the hormone,②body temperature,③Active inflammatory joint count,④ESE or CRP,⑤Physicians overall assessment of disease,at least the improvement ≥ 30% for 3 of them is considered effective,below the standards as poor efficacy or invalid,conducted a retrospective analy sis of clinical data of the effective and poor efficacy cases.