BackgroundExtensive research has confirmed the disadvantages of left-behind children in the development of human capital in rural China; however, evidence is limited on non-cognitive abilities, especially in the identification of causal effects. In recent years, the role of non-cognitive abilities on children has become increasingly prominent. ObjectiveThis study identifies the causal effects of parental migration and the decline of non-cognitive of left-behind children and explores the potential mechanisms. Participants and settingThe participants were 4636 rural students in the seventh and ninth grades of 43 secondary schools from 26 counties based on the China Education Panel Survey (CEPS) in the 2013–2014 academic year. MethodWe adopt an endogenous treatment effect model with the instrumental variable (IV) to identify the causal effects by constructing a comprehensive index to measure children's non-cognitive abilities based on the Big Five Personality Model. ResultsParental migration is significantly detrimental to non-cognitive abilities of rural left-behind children. Worse, except for agreeableness, the score of rural left-behind children in the other four sub-items is significantly lower. The negative impact of parental migration is partially explained by the fewer shadow education, the reduction in parent-child interactions, and the parental education participation, especially parent-child interactions in a major position. ConclusionOur findings are consistent with previous studies and further provide evidence that parental migration is the cause of the decline of non-cognitive abilities of rural left-behind children. These results indicate that it is necessary to formulate some public policies to focus on the neglected non-cognitive abilities of left-behind children.