A three-year-old, male Yorkshire terrier was presented with blindness, circling, hind limb weakness, and convulsive seizure for the past 3 months. Characteristic clinical findings were chronic, progressive neurological signs involving cerebrum and brain stem, an elevation of brain-type isoenzyme of serum creatine kinase, appearance of high voltage slow activity in electroencephalogram, and multifocal lesions in the cerebral hemispheres on magnetic resonance imaging. Necrotizing encephalitis of Yorkshire terrier was diagnosed after postmortem pathological examination. This is the first case report of the disease in Japan.