Objective: To compare the risk of posttraumatic stress (PTS) symptoms and the mediating effect of perceived future threat on the risk of PTS symptoms among survivors of pediatric cancer and children who had a parent die. Methods: Seventy-eight children (39 survivors of cancer, 39 bereaved) completed self-report measures of PTS symptoms, depression, anxiety, and perceived risk of future threat for the event they experienced. Results: The children who lost a parent reported significantly more PTS symptoms than the survivors of cancer. The effect of group status (survivor of cancer vs. bereaved) on PTS symptomatology was partly mediated by the children's perceived risk of future threat. Conclusions: The rate of PTS symptoms was found to be higher among children who had lost a parent than among survivors of pediatric cancer. This difference may partly be explained by their perceived risk of a future threat. Clinical implications are discussed. © The Author 2005. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved.