Background: Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy usually presents as meningoencephalomyelitis. Many patients developed flu-like symptoms preceding the neurologic symptoms. Reversible lesion in the splenium of the corpus callosum (SCC) is a clinical and radiological syndrome secondary to many kinds of etiologies, including infections, which is termed RESLES. Case presentation: we reported a case developing irregularly high fever, both temporal pain, low limbs fatigue with frequent urination admitted to our neurology department. CSF test showed GFAP-IgG positive, elevated WBC counts and protein, with low glucose and chlorine, while MRI showed a reversible lesion on SCC, leading us to diagnose autoimmune GFAP autocytopathy accompanied with RESLES. The boy had significantly improved after anti-virus and steroids therapy. Discussion: Autoimmune GFAP autocytopathy accompanied with RESLES is rarely seen, and pathogenesis for the co-existence has not been clarified. Autoimmune GFAP autocytopathy and RESLES are both related to viral infection. Our case covered infectious symptoms and improved after antiviral treatment, suggesting virus infection may perform a key role in pathogenesis.