The purpose of this study is to explain the progress of the Keirin importation plan in the Ryukyu Islands of a period of U.S. occupation. The subjects of this study are three points of the following. (1) Progress from the Keirin importation plan in the Ryukyu Islands of a period of U.S. occupation a plan to the abolition is researched. (2) Research into the reason why the Keirin importation plan was promoted. (3) Research into the reason why the Keirin importation plan couldn't be enforced The following three matters could be pointed out as a result of the study. (1) Progress from the decision of Keirin importation plan to the abolition reflected the diplomatic relations of Japan and the United States and the international situation such as the beginning of the political change of the East Asian region and the cold war. (2) As for the Keirin importation plan, a Japanese side was cooperating in Naha City and Ryukyu side. The purpose of Naha City was to make up for shortage of finance. A purpose on the Japanese side was to exercise a political influence and an economical influence in the Ryukyu Islands. (3) The development of Keirin importation plan stimulated USCAR (United States Civil Administration of the Ryukyu Islands). One of the causes that USCAR dismissed the decision of Naha municipal assembly which ignored public opinion is an inhabitant's Keirin counter movement