The authors describe a patient with an adamantinomatous craniopharyngioma (CPG) arising in the cerebellopontine angle (CPA), who also had probable Gardner's syndrome. This 31-year-old man presented with headache and dizziness. Brain CT and MRI showed a 5 × 4-cm lesion with multiple small calcifications in the left CPA. The patient underwent suboccipital craniotomy with tumor removal. Histopathological findings indicated an adamantinomatous CPG. This patient also showed characteristics of Gardner's syndrome. Although this syndrome is associated with intracranial neoplasms, it is unclear whether patients with both Gardner's syndrome and CPG are part of the heterogeneity of Gardner's syndrome.