Background: Suicide in adolescents has been identified as a serious public health problem worldwide.Across the globe about 200,000 teenagers deaths are due to suicide each year.The purpose of this study was to investigate the detection rate of suicidal ideation and explore the association between health risk behaviours and suicidal ideation of high school students in Lijin County, China.Methods: In November 2007, 1,378 students from two high schools in Lijin County were selected by using a stratified random cluster sampling method.The self-management questionnaire was used in this study.Chi-square tests, t-tests and logistic regression models were employed to identify the association between health risk behaviours and suicidal ideation.Suicidal ideation was defined as having considered committing suicide during the last year.Results: Overall, 13.5% of the sample with having suicidal ideation in the last year, and there was no significant difference between boys and girls in detection rate of suicidal ideation.Logistic regression analyses showed that nightmares (OR =1.05, 95% Cl =1.03-1.07), physical activity (OR =0.82, 95%Cl: 0.68-1.00) and sleep duration (OR =0.72, 95%Cl: 0.60-0.88)were significantly associated with suicidal ideation after adjusting for age, sex, physical health status, mental health status, parental education and family environment.Conclusion: The incidence rate of suicidal ideation among high school students is relatively lower than other reports.Sleep problems and lack of physical activity are the main health factors associated with suicidal ideation.The findings provide some evidence for formulating intervention program of suicidal ideation in high school students.