To better promote economic development, realize the freedom of population mobility and restore the function of population registration and demographic data statistics of household registration system, itÂs very necessary to deepen the reform of the existing household registration system centered on access conditions, eliminating urban and rural dual economic structure and promoting the formation of uniform urban and rural labor market. Moreover, under the background that overseas market demands are not sufficient, motivating domestic demands is put on the agenda. However, there is certain gap between the social welfare of urban residents and the one of rural residents, so urban-rural integration trend is restrained; meanwhile, urbanization lags behind the industrialization and citizensÂ rights and interests are widely noticed, etc. All these factors promote deepening the reform of household registration system. In this study, document analysis method, system inertial theory analysis method and comparative analysis method, etc. are used to make exposition. The study concludes that the direction of deepening the reform of household registration system is to reduce and then cancel urban access conditions and realize free migration of population finally under the precondition that impetus and conditions of household registration system change are met. Therefore, this study concludes the motivation and basic direction of deepening the reform of household registration system by the introduction of content, generation source and function of household registration system and stress on summary of reform pattern of household registration system in each city and analysis of difference of household registration system reform in each city.