Severe sensorineural hearing loss (bilateral >80 dB) was diagnosed in a case of familial hemophagocytic lymphohistiocytosis (FHL). The female patient developed HLH at 3 months of age and underwent allogeneic cord blood transplantation at 11 months of age following 7 months of immuno-chemotherapy. The type 2 FHL patient had a homozygous perforin gene mutation of 1090-1091delCT, and was noted to have hearing loss at 3.5 years of age. Retrospective evaluation did not clarify the exact causes of hearing loss. Reports on Kawasaki disease, suggesting a correlation between severe inflammatory status in infancy and the development of sensorineural hearing loss, may shed some light on this rare complication in this case of FHL. Considering the markedly improved prognosis of FHL due to recent advances made in the molecular diagnosis and in the management including allogeneic hematopoietic stem cell transplantation, auditor by screening might be warranted for surviving FHL patients.