The Interior Disease of Taeyangin(太陽人裏病證) is typical syndrome in the Taeyangin pathology taking nausea, vomiting and dyspepsia. However, The Interior Disease of Taeyangin is difficult to classify because Taeyangin patients are relatively few and published studies about Taeyangin pathology are rare. This patient was a 69-year-old man who had nausea, vomiting, dyspepsia and epigastric pain and had been diagnosed and treated as Gastric ulcer before. We classified this patient as The Interior Disease of Taeyangin and prescribed Mihudeungsikjangtang(??藤植腸湯). We experienced the good effect of Mihudeungsikjangtang on The Interior Disease of Taeyangin. We report the healing process and the result of treatment in this study.