Traumatic stress refers to physical and emotional reactions caused by events which represent a life threat or a disturbance of physical and phychological integrity of a child, as well as their parents or gaerdians. Car accidents are the main cause of posttraumatic stress disorder (PTSD) in children. The aim of this study was to preview clinical efficiency of systemic family therapy (SFT) as therapy intervention in treatment of children with posttraumatic stress disorder (PTSD) traumatized in car accident under identical circumstances of exposure. We pointed out the importance of specific family factors (family cohesion and adaptability, emotional reaction of the parents) on PTSD clinical outcome.