Abstract: ObjectiveTo investigate the current situation of sleep status and to examine its association with depression among high school students in Nanjing.MethodsClasses(n=168)from 56 schools were randomly selected in thirteen administrative districts/counties by population-based cross sectional study.Totally,7127 eligible participants were included in analyse.Depressive symptoms were measured using the 27-item CDI.ResultsThe average daily sleep time of adolescents was(8.3±3.5)h,90.8% them slept less than 9 h.The overall prevalence of depression(CDI)was 14.7% in the sample students,which was higher in boys(16.5%)than in girls(13.0%),while there was no difference between junior and senior high school students(14.5% vs 15.1%).After adjusting for possible confounding factors,a gradient decrease in adjusted odds ratios(ORs)of depression was found from <6 h to ≥9 h of daily sleep time.ConclusionAdolescent students have obvious insufficiency of sleep time in Nanjing.Sleep time was an independent protective factor depression among adolescent,and it was negatively associated with depressive symptoms.The sleep status of adolescents should be paid more attehtion to make them in good physical and mental health.