BACKGROUND Coronavirus disease (COVID-19) can cause various complications. We report a case of severe COVID-19 acute respiratory distress syndrome (ARDS) in a patient receiving veno-venous extracorporeal membrane oxygenation (V-V ECMO), complicated by Guillain-Barre syndrome (GBS) and cerebral infarction, as well as pulmonary embolism. CASE REPORT A 55-year-old Japanese man with a history of ulcerative colitis was admitted for COVID-19. His respiratory status worsened and progressed to ARDS, requiring intubation on hospital day (HD) 3. On HD 16, contrast computed tomography revealed PE. On HD 18, his respiratory condition worsened, and V-V ECMO was initiated. On HD 23, V-V ECMO was successfully discontinued. He regained consciousness on HD 44, but he had quadriplegia. Deep-tendon reflexes were absent in all limbs. Cranial nerve involvement, specifically bilateral facial nerve weakness, was noted. Magnetic resonance imaging showed bilateral scattered cerebral infarctions on HD 76. Nerve conduction studies indicated severe axonal neuropathy. Cerebrospinal fluid examination showed albuminocytologic dissociation. The antibody to the ganglioside GD1a was positive. These findings were consistent with the diagnosis of GBS. He received immunoglobulin treatment on HD 89, and his neurological findings slightly improved. CONCLUSIONS This study emphasized that in COVID-19, neurological complications are not rare, are difficult to diagnose, and are prone to delays in detection.