The large-scale population flow took place in 1980s of 20 Century has been one of most influential events for China’s economic society since reform and opening-up.According to fifth national census,there are 121.07 million floating population who spend more than half year on average outside of hometown.In the past 10 years,above 88.40 million rural labors achieved transformation to non-agriculture sections.According to National“11th Five Year”Plan,by 2010,China’s urbanization level will be up to 47% and there will be around 9 million rural labors enter cities every year.Such large-scale population transfer is unprecedented in the process of global urbanization and incomparable to America,Japan and any countries in Europe and South Asia.It brings forward severe challenges to construction of harmonic society in China.