We report two cases of cervical disc disease with myelopathy classified as of motor system syndrome type showing small contrast accumulation within the spinal cord on delayed CT myelography. In our two cases, high density spots on delayed CT myelography were bilaterally localized within the spinal cord, and believed represent pathological changes of the spinal cord, such as collection of microcavities or cystic necrosis. In case 1, the high density areas seemed to be localized in the anterior horn and corticospinal tract, and in case 2, they seemed to be localized in the corticospinal tract. The patient in case 1 produced signs and symptoms resembling motor neurone disease and lesion could not be differentiated from the latter. Delayed CT myelography showed that the cause of the upper limb amyotrophy was attributed to an anterior horn disorder and that of pyramidal tract sign to a corticospinal tract disorder. Therefore, we could differentiate the lesion from motor neurone disease on delayed CT myelography in case 1. In conclusion, we emphasize that delayed CT myelography can demonstrate the intramedullary pathological changes in the cervical disc disease and is useful in distinguishing between cervical disc disease simulating motor neurone disease and the latter.