Lhermitte-Duclos disease (dysplastic gangliocytoma) is a rare and slowly growing mass lesion in the cerebellum. We report a case of Lhermitte-Duclos disease with MR imaging. The mass lesion at the posterior fossa shows the characteristic MR appearance of the striated pattern of hyperintensity on T2-weighted images and hypointensity on T1-weighted images with slight enhancement. Thickened folia are present. These features on MR imaging may contribute to the correct diagnosis.