The thesis investigated the problems of Yunanese immigrants who fled from the 1949 Civil War between the Nationalist Army and the Communist Army. After the former was defeated, they retreated to Taiwan. Those in Yunan fled to Burma but were pressured to move to Taiwan while some migrated to Thailand. They caused so many problems that the Thai government issued regulations to control them under the supervision of the Interior Ministry. The Yunanese in Thailand were divided into three groups. The first group were former Nationalist Army officers. They were granted an alien status and their children Thai citizenship because the officers fought communist armies alongside Thai armies. The second group were Yunanese immigrants who were relatives of those officers. They were under the supervision of the Interior Ministry. This group often violated the regulations because they wanted to be free. They also wanted to have the regulations amended and to be given permission more easily or complete freedom to leave restricted areas because they had been there long enough. Moreover, they wanted to get Thai citizenship so that they wouldn’t have to follow the regulations. The third group were illegal immigrants and there were no policies to grant this group alien status or citizenship.