Background: Ferritin is a soluble protein which provides intracellular storage of bioavailable iron. It is found primarily in Liver, bone marrow macrophages, spleen. Ferritin is measured by ELISA, RIA and Mass spectrometry. The main aim of this study is to etiologically categorise extreme hyperferritinemia (serum ferritin > 10000 microg/L). Methodology and Results: This is 05 years retrospective study (July -2018 to June 2023), conducted in hematology section, MMCH, KSA. Out of 34 cases of extreme hyperferritinemia, viral infection was the most common cause comprising 41% of all cases. Amongst the infectious etiology, 6 cases of EBV, 3 cases of ALF of suspected viral etiology, 2 cases of PIDS with secondary infection, 1 case each of Hepatitis A virus and CMV noted. 10 cases presented as Macrophage Activating syndrome comprising 29% of total cases of which 70 were Systemic Juvenile Idiopathic arthritis and remaining 30% includes SLE and juvenile rheumatoid arthritis. Discussion: Study conducted by Dondu et al., indicate that the most common causes of hyperferritinemia are rheumatologic diseases and infections, which were identified in 59.1 and 27.3%, respectively. Present study showed infective etiology as the most common cause of extreme hyperferritinemia. Reasons for differences in results are because other studies were conducted in Adult patients and in Rheumatologic department. Conclusion: Our study formulated a systematic investigating pathway for raised serum ferritin. If the laboratory screening tests, BMA and other sophisticated tests are done in systematic way, then challenging cases can be diagnosed easily.