We report a 57-year-old woman with progressive gait disturbance and mental deterioration. She was well until March 1995, when she was 54 years of the age. At that time she noted a gradual onset of tremor and difficulty using her hand. Similar symptoms appeared in her right hands, and she visited another hospital, where 300 mg of levodopa and 7.5 mg of bromocriptine were prescribed. These medication did not help her symptoms. In the summer of 1996, she became to fall down easily. In September of the same year, she started to repeat the same words many times. She was unable to stop it. She was hospitalized to our service on January 25, 1997. On admission, she was alert but demented moderately; her Hasegawa dementia scale was 15/30. She showed palilallia, logoclonia, and echolalia. She showed constructional apraxia and questionable left-right disorientation. She had marked vertical gaze palsy with preserved oculocephalic response. She had masked face and small voice. Her gait was wide based with small steps. No muscle atrophy or weakness was noted. She showed only mild rigidity in the neck, but no rigidity was noted in the limb. No tremor was noted. She was bradykinetic. Deep tendon reflexes were symmetric and within normal limits. Laboratory findings on admission was unremarkable. MRI showed atrophy of the brain stem as well as cerebral cortical areas, particularly in the fronto-temporal region. Her hospital course was complicated with paralytic ileus and septicemia. She developed hypotension and pronounced dead on July 28, 1998. She was discussed in the neurological CPC. The chief discussant arrived at a conclusion that the patient had progressive supranuclear palsy and died of septic shock. All the participants wondered between PSP and CBD, but majority agreed with this diagnosis of the chief discussant. Only one thought that she might have had corticobasal degeneration rather than PSP, because of dementia, cortical atrophy in MRI, and lack of limb rigidity. Postmortem examination revealed cortical and brain stem atrophy. In the premotor cortex, marked astrocytosis and ballooned neurons were seen. Furthermore, astrocytic plaques were seen; this is considered to be pathognomonic for CBD. The substantia nigra showed marked neuronal loss and gliosis, but no neurofibrillary tangles or Lewy bodies were seen. Gliosis was also seen in the globus pallidus and in the medial thalamus. The pathologic diagnosis was corticobasal degeneration. This patient was very interesting case, in that the clinical manifestations appeared to be consistent with PSP, yet pathologic diagnosis was CBD. Lack of limb rigidity may be atypical for advanced PSP. In addition, palilalia appears to be more associated with CBD.