The pneumoperitoneum on the upright chest X-ray usually indicates a perforated viscus. As the peritoneal dialysis catheter provides an additional port of air entry into the peritoneal cavity, the incidence and clinical significance of pneumoperitoneum in peritoneal dialysis patients has been debated (a variable incidence from 21 to 33% has been reported in previous studies). We reported a 62-year-old female with diabetes mellitus and end-stage renal disease undergoing automatic peritoneal dialysis. In the night of 17 July, 2016, she experienced acute abdominal distension and pain during automatic peritoneal dialysis, and was admitted to our Emergency-Medicine Department. The abdominal computered tomography showed a massive pneumoperitoneum. Because a hollow organ perforation could not be excluded, an emergent exploratory laparotomy was performed. No intra-abdominal viscus perforation was noted. Therefore, technique-related pneumoperitoneum was impressed.