The recent development of a cell-based assay that can detect specific autoantibodies revealed the clinical features of diseases associated with the anti-myelin oligodendrocyte glycoprotein (MOG) antibody. The anti-MOG antibody associated diseases may include inflammatory demyelinating central nervous system diseases such as neuromyelitis optica spectrum disorders, optic neuritis, myelitis, atypical multiple sclerosis, and encephalitis. Among them, anti-MOG antibody associated cortical encephalitis may develop seizure as one of the primary symptoms, present unique lateral or bilateral medial frontal cortical lesions on brain MRI FLAIR images. In acute phase, steroid pulse therapy and anti-epileptic drugs are required. In chronic phase, immunosuppressive drugs are often required to prevent relapses.