It has been documented that posttraumatic stress disorder (PTSD) is common and representative posttraumatic reactions after traumatic event (e.g., earthquake). PTSD can be considered as pathological results after trauma, involving avoidance symptoms, negative cognitions and mood symptoms, hyper-arousal symptoms and re-experiencing symptoms. Life satisfaction is an important index to measure the quality of life, as an positive psychology, life satisfaction associated with psycho - mental factors such as depression, anxiety, PTSD , etc. PTSD can have pervasive, negative effects on multiple aspects of life satisfaction. Social support is one of the most important factor may affect the relationship between PTSD and life satisfaction. The current study investigated the relationship between PTSD symptom clusters and life satisfaction among adolescent survivors after the Ya’an earthquake. Moreover, we also further explore the moderating role of social support. The connection between earthquake-induced PTSD and life satisfaction has been studied by psychologists in recent years, who insisted that life satisfaction was significantly negative associated with PTSD. Although there seems to be a clear relationship between PTSD and life satisfaction after earthquakes, previous research in this area is somewhat limited. For example, many scholars pointed out the question of how PTSD influences the life satisfaction, but few of them had paid attention to the question of how the negative association between PTSD and life satisfaction may be avoided using social support. The present study was to investigate whether different symptoms of PTSD play different roles in life satisfaction, and whether social support moderated the relationship between PTSD and life satisfaction. Participant were 397 adolescents who were selected from several junior middle schools and senior middle schools in the county of Lushan, the area severely affected by the Ya’an earthquake. Participants completed The Revised Child PTSD Symptom Scale, Social Support Questionnaire, Traumatic Exposure Questionnaire and Satisfaction with Life Scale at 2.5 years after Ya’an earthquake. The main results were as following: after controlling for the age, gender and traumatic exposures, the results found that the re-experiencing symptoms, negative cognitions and mood symptoms, and hyper-arousal symptoms have significantly negative effect on life satisfaction, and the avoidance symptoms have no significantly predictive effect on life satisfaction. Social support has significantly positive effect on life satisfaction. In addition, the results also suggest that social support don’t moderate the relationship between re-experiencing symptoms of PTSD and life satisfaction as well as negative cognitions and mood symptoms of PTSD and life satisfaction, but the social support moderate the relationship between avoidance symptoms and life satisfaction as well as hyper-arousal symptoms of PTSD and life satisfaction. Specifically speaking, compared to individual with high social support, the avoidance symptoms and hyper-arousal symptoms have stronger predictive utility for life satisfaction among the individual with fewer social support. The present study supported conclusions from other papers that the different symptoms of PTSD may play different roles in life satisfaction, and social support moderated the association between some symptoms of PTSD and life satisfaction. The results have indicated that psychologists should take notice of the changes to lessen the PTSD of adolescents, and improve the social support of adolescents after traumatic event.