Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a new spectrum of autoimmune inflammatory nervous system disorders associated with infection, neoplasm, or drug use. We present the first pediatric case of GFAP astrocytopathy caused by an influenza A infection. The patient manifested meningoencephalitis, central respiratory failure, quadriplegia, elimination disorders, and syndrome of inappropriate antidiuretic hormone secretion. Methylprednisolone pulse therapy led to a good prognosis. In cases of progressive atypical complications of influenza infection, immunotherapy-reactive GFAP astrocytopathy should be considered as a differential diagnosis for prompt treatment.