since the first description about the retroanastomotic hernia with two cases report after gastroenterostomy in 1900 by Petersen, W., the Petersen's or retroanastomotic hernia has been reported by many other authors even though it is occurred infrequently, but very lethal complication after gastrectomy. In Korea, all 7 cases of the Petersen's hernia bad been reported untill 1975, since the first case report in 1968 by Dr. J.P. Kim. We also experienced two of the Petersen's hernia after gastrojejunostomy at the Department of Surgery, Presbyterian Medical Center in Jeon Ju; The first case was occurred 3 years postoperatively, and the case was found out on the eleventh postoperative day during hospitalization. Sox We report those two cases of the Petersen's hernia with a brief review of the literatures.