Lhermitte-Duclos disease (LDD) is a rare cerebellar lesion with features of both malformation and benign neoplasm. However, the fundamental nature of the entity, its pathogenesis, and the exact genetic alterations remain unknown. We describe a rare case of bilateral LDD with cerebellar ectopia and presyrinx spinal cord changes. Bilaterality of lesions should argue against a neoplastic origin and support a hamartomatous origin.