Spinal cord infarction is a sudden onset of myelopathy that manifests as motor dysfunction, abnormal sensation, and autonomic dysfunction. 1 Most patients with spinal cord infarcts experience causative events before symptom onset, but some do not. In 2019, Zalewski et al proposed new diagnostic criteria for spontaneous spinal cord infarction. 2 Since then, several cases in adult patients have been reported, 3 but children with this disorder have not been reported. Here, we report for the first time the case of a 10-year-old Japanese girl who fulfilled Zalewski's criteria for spontaneous spinal cord infarction.A 10-year-old Japanese girl, who was otherwise healthy and without any antecedent infection or injury, was referred to us. She also had no family history of hereditary neurological disorders.On day 1, she experienced abrupt pain in her neck and back while sitting alone in the morning, without any causative event. She could not walk independently and experienced hypoesthesia and numbness below the chest level by the evening. The next day, she was unable to maintain an upright position and exhibited urinary distention, and she was transferred to our hospital.On admission, she was alert and had stable vital signs. She did not exhibit any cranial nerve abnormalities. She needed assistance to walk and exhibited muscle weakness in the quadriceps, hamstring, anterior tibialis, and gastrocnemius, with grades 3+/3+, 3+/3+, 4/4, and 4/4, respectively, on manual muscle testing. She exhibited hyporeflexia in the lower extremities, and hypoesthesia for pain and temperature below the nipple level. However, position sense was preserved. The anal sphincter reflex was normal, and urination was possible.Blood examination yielded normal results. Cerebrospinal fluid (CSF) examination revealed normal cell counts and protein concentrations. The immunoglobulin G (IgG) levels in CSF was 2.0 mg/dL and IgG index was 0.68, showing normal range. Oligoclonal IgG bands were negative and the level of