We report a child with Sudden Infant Death Syndrome (SIDS), aged 16 months. The histological findings of tonsils, spleen, and bone marrow revealed many hemophagocytic cells. Parainfluenza virus type 2 (PIV2) was cultured in the nasopharynx and detected by reverse-transcription (RT)-PCR in liver tissue and bone marrow. His laboratory data of elevated level of ferritin and IL-6 suggested hemophagocytic syndrome (HPS). It is suspected that PIV2 infection in infants is a risk factor for SIDS.