Abstract: Rural migrant workers are a historical concept, whose titles are“Blind flow, Factory boys, Factory girls, Rural out employees”etc. The word of rural migrant workers spread widely and influence profoundly. Rural migrant workers' definition is uncertain which the existing literature considers from household register, career, industry, labor relations, wages and land etc. It is lack of discussing the relationship of these conditions and“rural migrant workers” further. This article considers rural migrant workers is the rural residents who are employed or engaged in individual manage in the place other than their hometown through extension and connotation and from the household register, land, flow, purpose and enterprise five aspects