In this essay, I tried to describe the process that the natural disasters and the state-running famine relief policy promoted the dual control system of Han empire. In doing so, I hoped to highlight the historical characteristics of Han Empire’s “contact zone”. At first, Han dynasty’s climate change was examined. From the former Han period, the average temperature has begun to drop, but the pattern of climate change took on a complex form. It became one of the causes of frequent natural disasters of Han times. And the cold weather caused great damage to the nomads of the frontier. Secondly, We saw that the natural disasters were one of the main factors that promoted dual operation of a commandery system of Han. The distinction between the inner commanderies and the frontier commanderies emerged from the state running relief policy against the famine disaster. The discriminatory relief policies have contributed to the creation of Chinese and non-Chinese ideas, to the Han chinese, the word ‘China’ meant only inner commanderies. The confucian intellectuals argued that in the event of a natural disaster, ‘the Chinese = the internal commanderies’ should be aided first and the frontier area should then be considered. This ideology was justified by the discriminatory view of Confucianism. The spread of Confucian ideology and the deterioration of the environment in the wake of the disaster seemed to have facilitated the dual operation of the empire. Third, I tried to describe the process that, since the latter half of former Han, the state affairs have been transformed into a more focused on inner chinese relief policy, rather than a frontline commandery. These changes were symbolized by the abolition of Zhu-ya-jun(珠崖 郡), the commandery in the Hainan island, long distance island from the capital, and the chang-ping-cang (常平倉), the grain warehouse in frontline. These things were happened in the early days of the emperor Won(元帝) regime. Since then, the state running relief policies had been confined to the inner counties. Approximately 72 disasters occurred during the 101 years - the latter half of former Han and the Xin times, about 30 of which were aided by the imperial government, and only two of them were occurred at frontline commandery. This limitation of the government relief policy to the inner commandery shows the Han empire’s dual control system of frontier and inner commandery.