The progress of the modern graphic technology is connected with better diagnosing of the pseudocyst of the pancreas in clinical practice. The pancreas pseudocysts are diagnosed accidentally in 20% of the patients in ultrasound examination, computed tomography, magnetic resonance imaging or endosonography; 24% of the patients reveal such abnormality in autopsy examinations. Pseudocyst is a complication occurring in 7–15% of acute pancreatitis patients. Usually they dissolve spontaneously, however, pseudocysts of diameter higher than 6 cm have a 30–50% risk of complications such as: rupture, bleeding and infection. Pseudocyst can turn in abscess in few weeks since acute pancreatitis. In this article we would like to present a case of spontaneous drainage of pancreatic abscess into gastric lumen. The treatment options for this entity are dictated by the severity of symptoms, the size of the pseudocyst, the ductal anatomy, and the surgical expertise available. Surgical drainage using open laparotomy or percutaneous drainage were the chosen treatment options. In most of the cases open surgical drainage should be reserved for patients in whom pancreatic necrosis, abscess, haemorrhage, or rupture of pseudocyst occurs. Transmural drainage using approach endoscopic ultrasound guidance is a technically feasible, minimally invasive, and safe procedure for drainage of pancreatic pseudocyst.