Objective: To understand the status and relationship between bullying behaviors and subjective well-being among left-behind students in Bijie,and to provide reference for the governments to support the development of policies and intervention. Methods: A total of 735 left-behind students were investigated on the spot with the Olweus Bully Questionnaire and Adolescent Subjective Well-being Scale. Results: Among the 735 left-behind students, 28.71% were found of participating in behaviors of bullying. More boys involved behaviors of bullying (bullies,victims and bully-victims) others than the girls(χ2=25.93, P<0.05), Bullying was more likely to be reported among children with poor peer relations(χ2=12.46, P<0.05). Total scores of the feelings of friendship，family，freedom,negative emotion and life differed significantly among different bullying roles(F=12.76, 2.86, 3.30, 5.98, 4.72, P<0.05). Multivariate analysis showed that there were many factors affecting the subjective well-being of these students, such as bullying behaviors, relationship with their classmates, academic record, the frequency which they contacted with parents(P<0.05). Conclusion Bullying is highly prevalent among left-behind children in Bijie. Effective prevention and control mechanisms should be established at the social, school and family levels to reduce the occurrence of bullying. Attention should be paid to the psychological and behavioral dynamics of left-behind middle school students, so as to improve their happiness.