Abstract: Based on the survey data of rural floating population over the years in CHNS database，this paper empirically tests efficiency of government assistance and public services for rural floating population. The result shows that public service can reduce poverty level of rural floating population from two aspects--the direct inreasement of income and the protection and inreasement of rights, personal income does not play a good role as a basis for targeting of poor rural floating population, government cash assistance has a strong crowding out effect on personal income of relative poverty rural floating population, absolute poverty rural floating population still has will to continue to work hard even if government cash assistance is obtained, effectiveness of it is different because of the internal differentiation of poor rural floating population, and government cash assistance and public services have a significant effect on shortening time of poverty reduction for absolute poverty rural floating population, but the effect of policies and measures is different, and the contribution of medical insurance is larger. In view of above findings, this paper make some suggestions. Firstly, integrated service model need to be established through integrating public services and cash assistance. Secondly,creating identification and targeting mechanism of rural floating population to improve targeting efficiency. Government should take different measures to save rural floating population, according to internal differentiation of them. To shorten poverty alleviation time of rural floating population of absolute poverty, it is important for government to focus on their medical risk when making polity.

Key words: urban and rural migrating population, government assistance, public service, poverty reduction