Many trials on various photographic and chemical treatment have been performed to get better quality of radiographs. Among them, subtraction techniue is a useful method for remonve the image of bone and soft tissue structures superimposed on blood vessel outlines. But in some angiographic examination, subtraction technique may be unhelpful due to respiration or movement of patient during injection of contrast agent. Thus, detail subtraction image is not produced as well as visibility of small vasxular lesion is diminished. To overcome these limitations, so called blurred undersubtraction (BUS) technique was tried in angiogram and other radiologic examinations. The results were as fololws: I) One angiogram, 1. Visibility of small blood vessels are improved by uniform background density, especially in high density area. 2. Outline of bone and blood vessels are emphasized by edge enhancement effect. 3. Comparing to conventional subtraction technique, BIS technique is easy to perform and needs no more equipments. 4. Comparing to conventional subtraction technique , no artifact is produced on BUS technique. ii) Cood quality images were obtained on radiographs of double contrast U.G.I., enema colon study and others. iii) Good quality images were obtained on paper print.