Background To review clinical characteristics, auxiliary examination results, treatment effects, and outcomes of patients with autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A). Methods We collated and retrospectively analyzed clinical data of 15 patients admitted with clinical characteristics of an autoimmune GFAP-A acute encephalitis or meningitis phenotype. Results All patients were diagnosed with acute-onset meningoencephalitis and meningoencephalomyelitis. Initial presentations included pyrexia and headache at onset; dual symptoms of prominent tremor with urinary and bowel dysfunction; ataxia, psychiatric and behavioral abnormalities, and impaired consciousness; neck resistance; reduced extremity muscle strength; blurred vision; epileptic seizures; and reduced basic blood pressure. Cerebrospinal fluid (CSF) examination showed that the degree of protein elevation was significantly higher than the degree of increase in white blood cells. Moreover, in the absence of obvious low chloride and glucose levels, CSF chloride levels decreased in 13 patients, accompanied by a CSF glucose level decrease in four. Brain abnormalities were found in magnetic resonance imaging of ten patients, with a linear radial perivascular enhancement present in the lateral ventricles of two patients and symmetric abnormalities in the splenium of the corpus callosum in three patients. Conclusions Autoimmune GFAP-A may be a spectrum disorder, with acute- or subacute-onset meningitis, encephalitis, and myelitis being the main phenotypes. When used for acute stage treatment, combined hormone and immunoglobulin therapy was superior to hormone pulse therapy or immunoglobulin pulse therapy alone. However, hormone pulse therapy alone without immunoglobulin pulse therapy was associated with a greater number of remaining neurological deficits.