| At the end of 12th Five-year Plan, the number of Chinese rural-urband floating population has reached 220 million。Large population mobility improved their living situation, but at the same time it gave birth to many poor floating population. Because of traditional system, most part of this poor people are often ezcluded from the scope of government assistance, and their living conditions have become increasingly difficult. So T it is imminent to form the government assistment mechanism to help poor floating population to improve their living condition. To formthemechanism, firstly,we should understand the interaction mechanism between the poverty of floating population and government assistment. Based on welfare enconomics and seleting data of rural-urband floating population in CHNS database, the study measured the poverty level of the floating population from perspectives of relative poverty and absolute poverty and established simultaneous equation model to describe the relationship between the poverty level of the floating population and the government assistance and Cox regression model to evaluate the effect of government aid policy on poverty alleviation of floating population and the efficiency of different policies, and then gave some policy advice.The result shows that public service can reduce the poverty level of the floating population from two aspects--the direct increase of income and the protection of the rights and the increase, personal income does not play a good role as a basis for the targeting of poor migrant population, government cash assistance has a strong crowding out effect on personal income of the relative poverty population, the absolute poverty floating population still has the will to continue to work hard even if the government cash assistance is obtained, the effectiveness of the government’s cash relief is different because of the internal differentiation of the poor floating population, and government cash assistance and public services have a significant effect on the shortening of the time of poverty reduction for absolute poverty population, but the effect of policies and measures is different, and the contribution of the medical insurance is larger.In view of the above findings, this paper make some suggestions. Firstly, integrated service model need to be established through integrating public services and cash assistance. Secondly,creating the identification and targeting mechanism of the floating population to improve the targeting efficiency. The government should take different measures to save floating population, according to the internal differentiation of them. To shorten the poverty alleviation time of the floating population of absolute poverty, it is important for government to focus on their medical risk when making polity. |