To investigate the role of self-esteem and empathy in the relationship between loneliness and cyberbullying among junior and senior school students.In the city of Shenyang, Chaoyang, Yingkou and Panjin in Liaoning Province, between March and May, 2017, a total of 961 middle school students from 12 to 18 age(grade 1 in middle school to grade 3 in high school) were selected by convenient sampling. Among them, there were 446 boys and 515 girls and there were 512 junior school students and 449 senior school students. Middle School Students' Cyberbullying Behavior Questionnaire(MSSCBQ), Rosenberg Self-Esteem Scale(SES), UCLA Loneliness Scale(UCLA) and Basic Empathy Scale(BES) were used for the study. The recovery data was analysed by independent sample t-test, correlation analysis, regression analysis and the structural equation model was established.(1) The male in the scores of cyberbully, cybervictim and loneliness were higher than the femal((17.1±7.0) vs.(14.8±5.6);(17.9±6.2) vs.(15.9±5.7);(45.2±9.7) vs.(42.9±9.8)), but the male in the scores in self-esteem and empathy were lower than the female((27.4±5.1) vs.(28.2±4.8);(63.1±9.5) vs.(66.0±11.0)) and the difference was statistically significant(P<0.05). The junior school students in the scores of cyberbully, cybervictim were higher than the senior school students((16.4±6.6) vs.(15.3±6.1);(17.7±6.0) vs.(16.0±5.9)), but the junior school students in the scores in self-esteem and empathy were lower than senior school students((27.2±4.5) vs.(28.5±5.3);(61.8±10.3) vs.(67.1±10.0)), and the difference was statistically significant(P<0.05).(2) The scores of CBQ, CBVQ and UCLA were positively correlated each other(r=0.20-0.33, P<0.01), and negatively correlated with the scores of SES and BES(r=-0.28--0.13, P<0.01).(3) Among junior and senior school students, the direct effect of loneliness on the cyberbully and cybervictim were 0.12 and 0.13. Self-esteem(indirect effect 0.09, 95% CI 0.37-0.79) and empathy(indirect effect 0.05, 95% CI 0.16-0.44) played mediating roles in the relationship between loneliness and cyberbully; Self-esteem(indirect effect 0.05, 95% CI 0.13-0.58) and empathy(indirect effect 0.03, 95% CI 0-0.03) played mediating roles in the relationship between loneliness and cybervictim.Negative prediction of self-esteem and empathy are to cyberbully and cybervictim, and positive prediction of loneliness is to cyberbully and cybervictim. The levels of self-esteem and empathy enhanced could mitigate the effect of loneliness on cyberbully and cybervictim.