Effects of Parental Migration on Mental Health of Left-behind Children: Evidence from Northwestern China

China's rapid development and urbanization have induced large numbers of rural residents to migrate from their homes in the countryside to urban areas in search of higher wages. It is estimated that there are more than 60 million "left-behind children" (LBC) remaining in the countryside after their parents migrate, typically living with surrogate caregivers. Extensive research has focused on the impact of parental out-migration on children's mental health, but less attention has been paid to the effects of parental return-migration. The present paper examines the changes in mental health before and after the parents of fourth and fifth grade students out-migrate or return-migrate. We draw on a panel dataset collected by the authors of more than 19 000 students from 252 rural primary schools in northwestern China. Using DID and propensity score matching approaches, our results indicate that parental out-migration has a significant negative impact on the mental health of LBC, as they tend to exhibit higher levels of anxiety and lower levels of self-esteem. However, we find that parental return-migration has no significant effect on the mental health of LBC.