Chylothorax is an infrequent pleural effusion often caused by traumatic or nontraumatic injury to the thoracic duct. Nontraumatic chylothorax caused by chronic lymphocytic leukemia (CLL) is rarely reported. Previous experience has implied that the main factor affecting the treatment of chylothorax is whether the anti-cancer treatment is effective. The patient diagnosed with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) before the hospital admission, and not received any treatment. After four months, he had progressive dyspnea. Chest computed tomography (CT) scan showed bilateral pleural effusion with progressive lymphadenopathy, and massive chylous pleural effusion was drained by closed thoracic drainage. After a course of chemotherapy including fludarabine, cyclophosphamide and rituximab (FCR), the patient developed agranulocytosis and his pleural effusion was still abundant. After careful consideration, the patient refused to receive following chemotherapy and chose to take ibrutinib orally. Two months after oral ibrutinib, ultrasound examination showed that pleural effusion completely disappeared. In the next one year, the patient had a routine follow-up and was in good condition. To our knowledge, this is the first report of ibrutinib in the treatment of chylothorax associated with CLL. Ibrutinib provides a more palliative treatment for elderly CLL patients with chylothorax.