Abstract Introduction Intracranial subdural empyema (ISDE) can cause drug-resistant epilepsy. We attempted to cure post-ISDE refractory epilepsy by operative surgery and assessed the neuropathological findings. Patient and method A 23-year-old right-handed man with refractory epilepsy had ISDE on the right temporal and occipital areas at 14 years old. He underwent ISDE drainage operation at the time. A week after the infection, he developed epileptic seizure, which consisted of epigastric sensation, followed by loss of awareness with gelastic seizure. This type of seizure occurred around five times a day. He underwent right posterior disconnection and the temporal lobe was submitted to histopathological examination. Result The patient has remained seizure-free for more than 3 months. Histopathological diagnosis showed focal cortical dysplasia (FCD) type IB. Conclusion We cured post-ISDE refractory epilepsy by posterior quadrant disconnection. Epileptogenicity of FCD might be triggered by ISDE.