Hemophagocytic syndrome (HS) and Adult-onset Still’s disease (AOSD) are both rarely systemic inflammatory disorders. It may be difficult to differentiate these inflammatory disorders from each other. There are some signs that may help clinicians in the diagnosis such as high ferritin levels for AOSD, and leukopenia, thrombocytopenia, hypertriglyceridemia for HS. Hemophagocytic syndrome secondary to Adult-onset Still’s disease was reported rarely in literature. In this article, we aimed to report a patient of 65-year old female diagnosed with HS and AOSD with extremely high serum ferritin levels.