It was analyzed the features of different forms of acute pancreatitis in 1001 patients including 324 cases with pancreatonecrosis and 245 patients with middle severity of disease. It was shown that monitoring of patients' condition and destructive process in pancreas by using of modified SOFA-scale and evaluation of sonographic signs of inflammation are advisable. Flow indicators including resistance index and the maximum flow velocity in celiac trunk and superior mesenteric artery represented severity of gland's destruction. Sonographic investigation revealed small-focal pancreonecrosis. It allows to differentiate medical tactics. Surgical treatment was performed in 582 patients. Efficiency of surgical treatment is determined by diagnostic methods, timely sanation of destructive focuses of pancreas, abdominal cavity, retroperitoneal fiber, adequate drainage and mini-invasive techniques using in case of purulent complications. The main prognostic factors of development of complications and adverse outcomes are determined.