Brain tumor in combination with cortical dysplasia is one of the causes of epilepsy, but coexistence of these two entities is a rare event. We report a case of pleomorphic xanthoastrocytoma (PXA) arising in combination with Taylor-type IIB-focal cortical dysplasia. A 54-year-old male had been suffering from temporal lobe epilepsy for 40 years. Nine years ago (at the age of 45), a brain CT revealed a mass (1cm) in the uncal area, but the patient did not give consent to an operation. Later, he was admitted as an emergency case because of severe headache, and the tumor was removed. The tumor was diagnosed as PXA with anaplastic feature (mitotic count: 5/10HPF), and the brain around the tumor showed dysmorphic neurons and balloon cells. Therefore, the tumor was assumed to be associated with the brain, with Taylor-type-IIB focal cortical dysplasia. The patient's condition deteriorated, with tumor recurrence and widespread leptomeningeal seeding to the whole spinal cord. He died 17 months after tumor removal.