A-65-year old woman who developed total ophthalmoplegia, areflexia in all her limbs and ataxia after upper respiratory tract infection was admitted to our hospital on the second day of illness. On day 3, she developed severe tetraparesis and respiratory failure which required mechanical ventilation, and Guillain-Barré syndrome (GBS) was diagnosed. On day 4, bilateral ptosis, facial diplegia, and neck muscle weakness appeared, and her all limbs were flaccid and immobile. An electrophysiological study suggested axonal damage. Marked blood pressure fluctuation also appeared on day 4. On day 5, an electrocardiogram showed a ST-segment elevation in leads V1 through V4 and the echocardiography showed anterior hypokinesia of the left ventricle. Her serum creatine kinase was normal. Left ventricular dysfunction and ST-segment elevation were normalized within hours, but a transient ST-segment elevation re-occurred on day 6. An electrocardiogram on day 13, showed inverted T waves in diffuse leads, which inversion continued. ST-segment elevation and hypokinesia in this patient were restricted to the left anterior descending branch, therefore, coronary spasm of that branch was considered the possible mechanism. In contrast, inverted T wave was due to either catecholamine cardiotoxicity or diffuse cardiac ischemia. Abnormalities of electrocardiogram were presumably due to cardiovascular autonomic dysfunction of GBS.