Objective: To investigate association between adolescent depressive symptoms with circadian rhythm and emotion regulation strategies, and to provide the basis for mental health education for depression. Methods: CES-D, Morning and Evening Questionnaire-5 (MEQ-5) and Emotion Regulation scale (ERS) were administered to 2 398 students from 6 middle schools in Chengdu, Langzhong and Leshan of Sichuan Province. SPSS 21.0 was used to data processing and anlysis. Results: About 37.9% (909/2 398) of adolescents reported depressive symptoms. Prevalence of depressive symptom was higher in female students( χ 2= 25.15 , P <0.01), rural adolescents( χ 2=15.45, P <0.01), adolescents aged 15-18 compared to aged 12-14( χ 2=187.24, P < 0.01 ). There was significant difference in rate of depressive symptoms among adolescents with different circadian rhythms( χ 2= 55.19 , P < 0.01 ), with definite evening rhythm preference was the highest(57.1%). Prevalence of depressive symptoms significantly varied by sleep duration( χ 2=141.99, P <0.01), and were highest in adolescents with sleep duration <6 h(69.4%). The scores of suppression dimension in depressed adolescents were significantly higher than that of non depressive group, while the scores of reappraisal dimension were significantly higher in non depressive group than that of depressive group. Multivariate Logistic regression analysis showed that gender( OR =1.60), age( OR=2.29), suppression( OR = 1.13 ), sleep duration <6 h( OR =5.17), sleep duration 6-8 h ( OR =2.88) were positively associated with depressive symptoms in adolescents. Moderate type( OR =0.53), morning type ( OR =0.55) and cognitive reappraisal ( OR =0.90) were associated with lower rate of depressive symptoms( P <0.05). Conclusion Sleep rhythm delay, lack of sleep and emotion suppression in adolescents are associated with higher risk for depression. Regular sleep habits and reasonable emotion regulation might help to prevent adolescent depression.