BACKGROUND Idiopathic basal ganglia calcification, also known as Fahr's disease or Fahr's syndrome, is a rare neurological disorder characterized by abnormal calcified deposits in the basal ganglia. Here, we report a case of Fahr's syndrome with calcification of the basal ganglia due to hypoparathyroidism in a patient with seizures. CASE REPORT A 52-year-old male patient visited our clinic with seizures. Brain computed tomography (CT) showed bilateral symmetrical calcifications in cerebellar white matter, the corpus striatum, the posterior thalami, and the centrum semiovale of both cerebral hemispheres. He had symptoms of hypocalcemia and low parathyroid hormone levels. The patient was diagnosed with Fahr's syndrome due to primary hypoparathyroidism. He underwent calcium supplementation and calcifediol treatment. His symptoms improved, and he was discharged from the hospital. CONCLUSIONS In patients with hypocalcemia accompanied by parathyroid dysfunction, neurological examination and CT should be performed to confirm abnormal intracranial calcification.