A case of Creutzfeldt-Jakob disease (CJD) is reported in a 48-year-old woman who had received a cadaveric dural graft after a clipping procedure of a cerebral artery aneurysm in September 1985. In November 1994, she noticed unsteady gait and blurred vision at first. She successively developed ataxic gait, dementia and myoclonus, and became mute. Serial CT scans revealed no abnormal findings, and serial EEGs showed diffuse slow activity without periodic discharge. The patient died in March 1996, 17 months after the initial symptoms. A brain autopsy demonstrated extensive spongiform degeneration in the cerebral neocortex, thalamus, striatum, and cerebellum especially in the granular layer, with associated astrocytosis and marked neuronal loss. Immunohistochemically, PrP plaques, so called kuru-type plaques, were extensively distributed throughout the cerebrum and cerebellum. Moreover, some of these plaques resembled "florid" plaques, which were surrounded by a zone of spongiform change. The PrP gene analysis of her blood and brain tissue revealed no mutations with homozygosity, Met/Met, at codon 129. The unusual features of this case, that is the absence of PSD on EEG and the widespread presence of kuru-type plaques including "florid" plaques, may be similar to the features of "new variant" CJD.