Abstract: The citizenization of rural migrant workers is an inevitable trend in the process of urbanization. The essence of the citizenization of rural migrant workers is to make sure rural migrant workers enjoy the same public service after realizing citizenization. And assessing the cost of the citizenization of rural migrant workers is conducive to better promote the process of urbanization. By conducting a survey on small and medium cities in He'nan Province, this paper analyzes the factors influencing the social cost of the citizenization of rural migrant workers and it also analyzes the social cost of the citizenization of rural migrant workers based on the measurement of the areas and the type of rural migrant workers, offering some countermeasures and suggestions on the citizenization of migrant workers.