‘Japanese pirates(倭冦)’that was active on the stage of East Asia, it is treated as the common subject in the history of Korea, China, Japanese. However, there is considerable difference in the image about Japanese pirates written by the the historical description of each country. The different views of the Japanese pirates between Korea and Japan and China are associated with situations of the past. If the discrepancy between the Japanese pirates of the present and past is due to the specific reasons, they would be important clues that make a close investigation into the discrepancy between the present and the past as well as Korea and Japan. The current image of Japanese pirates was managed by accumulation and a change of the memory for a long time. Therefore, for the understanding of the current image, it is necessary to know what happened in the past. In Japan, there are many research products of the Japanese pirates, but there is little research of that before 1945. The researches of the Japanese pirates before 1945 were understood ambiguously, so this situation aroused the misunderstanding about research of the past. The reason why the Japanese pirates caught the interest in Prewar Japan　had close relation to Japanese reality.　So the analysis for the Japanese pirates was more likely to change by the situation.　Prewar Japan encountered a sudden change for the inside and outside. In such a change, how was the explanation for the Japanese pirates changed? How was the Japanese pirates explained?　And does it have what kind of relation to the image of Japanese pirates that we have? In this sense, it is a meaningful study that investigates the change of the view of the Japanese pirates in Prewar Japan.