A 2-year-old girl had a craniopharyngioma removed in 1964. She received human growth hormone (HGH) twice a week from July, 1972, until July, 1976. In March, 1984, a subacute dementing illness developed with neurological signs that included pronounced cerebellar ataxia. A clinical diagnosis of Creutzfeldt-Jakob disease (CJD) was made. The patient died in February, 1985. Necropsy revealed a spongiform encephalopathy compatible with the transmissible form of CJD. HGH administration may be implicated in the transmission of the disease in this case.