Abstract With increasing number of migrant in our country, children of migrant workers, including left-behind children and migrant children, are rapidly and dramatically rising. There are some psychological and behavioral changes with the children left away from their parents or entered the city with his parents. People are paying more attention to this special group. In this study, we investigated 539 children of migrant workers and 210 children of control group in Shaanxi Province, using California Healthy Kids Survey Resilience Assessment Module and Sense of Security Scale. We also analyzed the effect of psychological resilience on sense of security. The results were as following: 1. The migrant children’s psychological resilience and sense of security were significantly lower than those of the control group and left-behind children. There was no difference on the level of psychological resilience between the left behind children and the control group, but their levels of sense of security were significantly lower than the control group children. 2. Psychological resilience of female left-behind children was higher than male children. No gender differences on psychological resilience were noted among migrant children. 3. Psychological resilience of children of Shaanxi migrant worker, having closest relationship with their parents, was higher than children with closer relationship to their parents. 4. Sense of security among female migrant children was higher than male, but no gender differences were found in left-behind children. 5. The migrant children with good parent-child relationship have higher sense of security than the children with bad parent-child relationship. The same pattern was not noted among left-behind children. Sense of security in Shaanxi migrant workers’ children, having closest relationship with their parents, was higher than children with closer relationship to their parents. 6. Psychological resilience of the children of migrant workers and the existence of the external protection factors (family and social) can significantly predict their sense of security. This research analyzed the effects of factors such as gender, marital relationship, parent-child relationship on migrant children psychological resilience and sense of security and the relationship between psychological resilience and sense of security. The present study found that Shaanxi migrant children psychological resilience level was relatively low, migrant children's security level also needed to be improved, and psychological resilience was one of the important protective factor promoting migrant children’s sense of security. Our study provided scientific bases for family education and school mental health education of the migrant children and left-behind children; the study also provided theoretical support to improve the mental health of the children of migrant workers.