Abstract The patient, a male in his 70s, was referred to our hospital after an upper gastrointestinal endoscopy revealed esophageal cancer. After a close examination, he was diagnosed with esophageal squamous cell carcinoma T3, N2, M0, Stage III. After preoperative chemotherapy, he underwent thoracoscopic esophagectomy and gastric tube reconstruction. Intraoperatively, the thoracic duct was injured on the cranial side of the aortic arch and was ligated with a clip. When tube feeding was started postoperatively, a pleural effusion was observed, and the patient was treated with central venous nutrition. The effusion did not improve, so thoracoscopic surgery was performed on the postoperative day 12, and the thoracic duct was ligated just above the diaphragm. Postoperatively, the patient developed ascites in addition to pleural effusion, and continued to totally drain 3000 mL of thoracoabdominal fluid every day. Lymphangiography showed that lymphatic flow was interrupted at the site of thoracic duct ligation, but the site of leakage was unknown. Based on previous reports, octreotide 300 μg and etilefrine 100 mg was administered continuously, and pleural drainage decreased, and ascites drainage increased. Ascites volume exceeded 3000 mL in three days and was treated with a single puncture, but no improvement was observed. Tolvaptan 3.75 mg was started, and ascites decreased gradually. Patient’s general condition improved with nutrition and rehabilitation, and he was discharged on the day 189. We report a very rare case of refractory massive ascites following thoracic duct ligation for postoperative chylothorax, along with a discussion of the relevant literature.