The situation of technology predominance and the distribution of core technology were visually mapped through the investigation of technical trend during last twenty years with the central point of patent information for ethanol preparation. Therefore, it is expected that technology mapping by means of multilateral analysis method allows a good grasp of current technology trend of ethanol preparation and the subdivision into nation and a field of research presents the direction of R＆D. Also the mutual relationship between research areas was investigated by making a comparison between the number of application of patent and that of literature.