Introduction: In 1899, William S.Halsted of The Johns Hopkins Hospitaldescribed a transduodenal local ampullaryresection with reanastomosis of thepancreatic and bile ducts to the duodenumin a patient presenting with obstructivejaundice.During the 1940s and 1950s,pancreaticoduodenectomy was performedin limited numbers with variable results. Atthat time, the operation carried a hospitalmortality that approached 25% in someseries, leading some authorities to abandonthe procedure. In the last several decades,improved hospital morbidity, mortality, andsurvival after pancreaticoduodenectomy havebeen reported. Many centers now reportoperative mortalities of less than 4% [1].Pancreatic adenocarcinoma is the 4th leadingcause of cancer death in the United States.The National Cancer Institute estimated thatthere were 43,140 new cases of pancreaticcancer in the United States in 2010 andthat pancreatic cancer was responsible for36,800 deaths [2].In Mongolia pancreaticcancer is uncommon disease and pancreaticadenocarcinomas incidence in Mongolia100’000 : 2,4; therefore 85% cases arediagnosed in unresectable stage [3].Materials and methods: Weretrospectively reviewed and calculated withstata13.0for patients(n96) who underwentresections (PD by Whipple operation) ofperiampullary (pancreatic, CBD and ampullaeVater) tumorsin HPBSD of Cancer CenterMongolia between 2008-2016.Results: This was retrospective chartreview of 96 patients treated withinthe Hepato Pancreatico Biliary SurgeryDepartment of Cancer Center Mongolia from2008 to 2016. Patient demographics andrelevant patient history including age, sex,date of birth, race, and co-morbidities weredocumented. Inpatient variables included thedate of procedure, complications, lengthof stay in the intensive care unit (ICU) andhospital, and disposition after discharge.At the time of the study total number ofHPBSD operations were 2963, thereforeall pancreatic and periampullary operations251(8,4%), Whipple operation 96 (3,2%)wasperformed. The operative and perioperativecharacteristics for patients who underwentpancreaticoduodenectomy n96(38.2%for all pancreatic and periampullaryoperations n251), 2008-n3(3,1%),2009- n7(7.2%), 2010-n13(13.5%);2011-n16(6.2%);2012-n10(10.2%);2013-n112(12.5%);2014-n19(19.8%);2015-n13(13.5%);2016-n13(13.5%); were meanage 54, sex ratio/m:f/ n47(49%):n49(51%),mean hospital stay 20, mean operationtime 434.5min, mean operative blood loss333ml. In the histological review werepancreatic adenocarcinoma 60%, ampullaeVater adenocarcinoma 20%, common bileduct adenocarcinoma 4.3%, benign or insitu tumours (IPMN, pancreatic adenoma,cystadenoma, and Frantz tumor(SPN) etc.)14%. The perioperative mortality(definedas death in hospital or within 30 daysof discharge) for patients undergoingpancreaticoduodenectomy wasn=6(6,2%)and perioperative morbidity or complicationrate was n=39(40,6%). At the time of ourstudy period complications were occurredwith DGE n4(4,1%) bleeding n3(3.1%),abdominal abscess n1(1%), gastric fistulen1(1%), stenosis of gastric anastomosisn1(1%), hypoglycemic coma n1(1%),pancreatic fistule n14(14,6%), perforation ofsmall intestine n1(1%), pneumonia n1(1%),ascites n1(1%) and post-op complicationsneeded secondary procedures : relaparotomyn=12(12,5%) .Only wound infection werethe most frequent complication15(15,6%) .Conclusion: Since 2009, in CancerCenter Mongolia, we are using new methodthat “mucosa to duct” modification forpancreatojejunostomy with protectionby decompress drain in Wirsung duct forpancreaticoduodenectomy is very beneficialmethod to decrease pancreatic fistulecomplication rate and it was a big stepto develop of pancreatic surgery field inMongolia. The our mean hospital stay(20days) after Whipple operation is not toolong with compare other countries (23-27)[2]. Until now, in Mongolia doesn’t have anycomplete studies about results of surgicaltreatment for pancreatic cancer and ourstudy needs completion, to improve and tocontinue.