We report a fatal case of acute lower respiratory tract disease with human rhinovirus C (HRV-C) as the unique cause in a 19-month-old girl with a history of repeated episodes of bronchiolitis. HRV-C type 8 nucleic acids were observed in respiratory, stool, and cerebrospinal fluid samples, and infectious virions were isolated from patient serum after inoculation onto reconstituted airway epithelia.