Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome and is classified into primary and secondary HLH. Primary HLH includes monogenic problems that especially have an effect on the perforin-mediated cytotoxicity of cytotoxic T lymphocytes and herbal killer cells. Secondary HLH happens as a difficulty in diverse settings together with infection, malignancy, autoimmune disease, and postallogeneic hematopoietic stem mobileular transplantation. Both primary and secondary HLH are characterized via way of means of out of control hypercytokinemia that affects myelosuppression and vascular endothelium damage. The maximum not unusual place shows of HLH are continual fever refractory to antimicrobial retailers and hyperferritinemia because of hypersecretion of diverse cytokines. To enhance outcome, it is miles critical to discover the problems underlying HLH and offer disorder-suitable treatment.