Abstract: Based on the questionnaire survey data of rural children in J County, S Province jointly carried out by the research group of Xi'an Jiaotong University and Southwestern University of Finance and Economics, this paper compares and analyzes the differences in health between left-behind children and non-left-behind children. The study finds that, the health status of the two types of children differed in all dimensions. First, in terms of physical health, limited by economic development in the surveyed areas, the surveyed children generally have certain nutritional problems, but there is no significant difference in physical health of left-behind children and non-left-behind children. Secondly, in terms of mental health, the loneliness and depression of left-behind children are more prominent. Thirdly, in terms of social adaptation, left-behind children have stronger social adaptation ability, social communication ability and efficient execution ability. Fourthly, fathers and mothers play different roles in healthy development of children. It can be seen that the impact of parents' going out on health of left-behind children has two sides. Therefore, in the future, the first thing to be done should be to improve public health services and attach more importance to children's medical care. Next is to improve the frequency of parent-child contact and strengthen effective parent-child communication. Finally, school and community care should be strengthened to encourage children to engage in social activities.