AbstractHere we report the cases of five patients on continuous ambulatory peritoneal dialysis (CAPD) who developed hydrothorax because of pleuroperitoneal communication. Preoperative computed tomography (CT) peritoneography revealed penetrated sites on the diaphragm in all patients. All patients underwent video‐assisted thoracoscopic surgery (VATS), and a dialysate containing indigo carmine was injected intraperitoneally through a CAPD catheter to confirm the fistula. In all patients, a thinned bleb was found at the center of the diaphragmatic tendon consistent with that noted on preoperative CT peritoneography. The bleb was resected using a surgical stapler in four patients, and the pleuroperitoneal communication did not recur. However, in one patient, the bleb was only covered with reinforcement agents and the hydrothorax recurred after CAPD. This study demonstrates that VATS treatment for pleuroperitoneal communication is safe and effective but that lesion resection would be more useful for preventing hydrothorax recurrence in patients undergoing CAPD.