The accurate diagnosis of anti-myelin oligodendrocyte glycoprotein (MOG) antibody-associated diseases is sometimes challenging due to its various central nervous system (CNS) lesions. Here, we report a 22-year-old man with positive anti-MOG antibody presenting multiple brain lesions including a brainstem tumefactive demyelinating lesion (TDL), cortical edematous lesions, and a periventricular white matter lesion. These variety of lesions made the diagnosis challenging, especially because TDL is quite rare among MOG antibody-associated disease patients. The present case suggests the importance to check anti-MOG antibody for patients presenting atypical multiple CNS lesions.