Various problems related to migrant or left-behind children are largely associated with family patterns and children’s living arrangement.Using data from a 2006 survey of migrant workers in Pearl River Delta,this paper explores determinants of migration probability of children of migrant workers.Results show that being migrant or being left-behind is significantly associated with children’s age,rural social support,migration distance and living status of their parents in the cities.The decision of being migrant or being left-behind is a rationale choice of children’s parents,which is also determined by institutions at the national and local level.Consistent with the "pull-push" theory of migration,migration of children of migrant workers is an outcome of the combination of the pulling factors at rural areas and the pushing factors at the urban areas,while also being a trade-off decision of their parents.