A 53-year-old man presented with massive right hydrothorax just after introduction of continuous ambulatory peritoneal dialysis (CAPD). Because the glucose concentration of pleural fluid was markedly high compared with that of serum, we diagnosed pleuroperitoneal communication. Thoracoscopic surgery was performed and thinning of the diaphragm was found. We sutured the diaphragm to repair the thin portion and performed pleurodesis with 50% glucose solution. He restarted CAPD 1 month post-operatively and continued at home without pleural effusion. Eight months post-operatively, he experienced dyspnea again and chest X-ray showed right hydrothorax. Although the cause of recurrent hydrothorax is unknown, it may be that not only surgical repair but also more intense pleurodesis is needed.