Unfortunately, many patients may have persistent pain lasting for many months, or even years, following thoracic surgery. No effective treatment has so far been established for chronic pain after thoracotomy. There are no reports of treatment involving Pregabalin for pain after thoracic surgery. This study reports four cases that showed significant improvement with Pregabalin in late-onset (notified during an office visit after discharge) nocturnal insomnia and in stress-induced ulcers caused by intercostal neuralgia after thoracotomy.