Abstract: Based on the survey of more than two thousand migrant workers from the Pearl River Delta and Yangtze River Delta in 2010, according to “welfare triangle”, this paper found that the variables among household variables- the number of children and the land scale owned by a family have obvious significance on migrant worker’s participation wish. The variables among work variables- type of work, whether to sign the labor contract and their seniority have appreciable compact on migrant worker’s participation wish. The variables among personal urbanization willingness variables- whether want the permanent urban residence certificate and the future plans have a marked impact on migrant worker’s participation wish. In addition, migrant worker’s valuation of social welfare provided by governments also has a significant impact on their participation wish. At last, this paper argued that in order to improve urbanization , the government should turn the amphibious social security system of migrant workers into national social security system.