Hemophagocytic lymphohistiocytosis (HLH) is a rapidly fatal disease caused by immune-dysregulation characterized by hypercytokinemia, with about 30%-40% of patients suffering death in children. Stratification strategy and individualized treatment is important to improve the survival. In our recent retrospective study, risk stratification based on IL-10 and IFN-γ levels well distinguished patients with different outcomes. In this multicenter prospective study, we will enroll the newly diagnosed pediatric HLH patients and divide them into low, intermediate and high-risk cytokine groups according to IFN-γ and IL-10 levels. The patients'clinical manifestation and laboratory findings will be further evaluated into severe and non-severe groups. For low/intermediate risk and non-severe patients, steroid or ruxolitinib will be used initially; while those with high risk or severe diseases, DXM+VP16±ruxolitinib will be administered. The treatment strategy could be adjusted after evaluation 48-72 hours later.