Background: It is unclear about the long-term change and risk factors of suicidal ideation, posttraumatic stress disorder (PTSD) and depression symptoms among adolescent survivors after the 2008 Wenchuan earthquake in China.This study is to explore the time trends and risk factors of suicidal ideation, PTSD and depression symptoms among adolescent survivors after the earthquake.Methods: The suicidal ideation, PTSD and depression symptoms among high school students at 6, 12 and 18 months after the Wenchuan earthquake were investigated.Subjects in this study included 737 student survivors in an affected high school by the earthquake.The PTSD Checklist-Civilian Version (PCL-C) and the Chinese Beck Depression Inventory (C-BDI) were used to measure the symptoms of PTSD and depression.Results: The rates of suicidal ideation among the student survivors at 6-, 12-and 18-month after the earthquake were 35.6%, 35.6% and 30.7% respectively.Significant decreases in the rates of PTSD symptoms were noted at 6-, 12-and 18-month after the earthquake (32.3%, 11.1% and 9.1%), while the rates of depression symptoms at 6-, 12-and 18-month after the earthquake were 57.8%, 53.7% and 44.7% respectively.Being female, having been injured, having family member injured, having PTSD and depression symptoms were significantly associated with suicidal ideation.Conclusion: Although the rates of PTSD symptoms among adolescent survivors decrease significantly 12 months after the earthquake, the rates of suicidal ideation and depression symptoms still maintain in a higher level 18 months after the earthquake.The disaster-related psychological sequelae may last for many years, long-term suicide prevention in adolescent survivors should be further developed, and the risk factors of suicidal ideation should be considered in the mental health services and interventions.