We report a case of an 85-year old man with an adenocarcinoma of the rectosigmoid colon (clinical stage II). Though tumor was resectable, the patient was considered to be inoperable because of old age and comorbidities such as asthma, diabetes and old myocardial infarction. He wanted to receive alternative care, so he was exclusively treated with standardized Allegern-removed Rhus verniciflua Stokes (aRVS) extract and other herbal medicine such as BOJUNGIKGI-TANG GAMIBANG. During 18 months, he has shown good performance status without transfusion. This report suggests that herbal treatment including standardized aRVS for rectosigmoid colon cancer could be an alternative treatment option when it is unabled to be treated by surgical resection.