Two domestic shorthair littermate kittens had signs of cerebellar dysfunction, first observed between seven and eight weeks of age; a third littermate was unaffected. The signs were progressive and the more severely affected kitten was euthanased after six days. A postmortem examination revealed no gross lesions but the kitten had cerebellar cortical degeneration with extensive loss of Purkinje cells. The second kitten was euthanased at 10 months of age with similar, though more pronounced, changes. One of the two kittens in the next litter of the same parents had similar clinical signs and histopathological findings. The lesions in the cerebellum are interpreted as probably due to genetically determined abiotrophy. In addition, the two older kittens had medullary neuronal changes interpreted as probable neuraxonal dystrophy, and focal vacuolation of the neuropil in the medulla and cervical spinal cord.