Acute necrotizing encephalopathy (ANE) is a rare clinical-imaging syndrome with unknown etiology, characterized by acute fulminant severe encephalopathy and brain damage with multifocal symmetry. ANE has no specific clinical symptoms and signs, similar to common encephalitis or encephalopathy symptoms. The characteristic brain imaging examination is diagnostically significant. To date, no specific treatment for ANE is available and the prognosis is poor. Here, we reported a typical case of ANE in a child, in whom good outcome was achieved via combined therapy with immunoglobulin and glucocorticoids.