Tension pneumoperitoneum is a severe and rare form of pneumoperitoneum with concomitant hemodynamic instability and respiratory failure. It is a variant of abdominal compartment syndrome (ACS) causing an abrupt increase in intra-abdominal pressure.We present a case of pneumoperitoneum, after an endoscopic mucosal resection with the development of ACS. The patient was successfully treated with percutaneous decompression.Decompressive laparotomy is the first treatment option for both most forms of pneumoperitoneum and ACS; nevertheless, this issue is controversial. Recent reports have shown that some patients may be candidates for a minimally invasive catheter decompression avoiding major decompressive surgery. Identifying these patients is vital to avoiding unnecessary surgeries.Tension pneumoperitoneum is a life-threatening event, early detection and intervention is critical in order to provide prompt and optimal treatment approaches.