The present study examined variables contributing to perceived benefits in the aftermath of traumatic events or posttraumatic growth (PTG) in U.S. (N = 182) and Japanese (N = 163) college students. Specifically, PTSD symptoms (intrusion, avoidance, and hyperarousal), optimism, and number of traumas experienced were examined in relation to posttraumatic growth. The results showed that in both samples, PTSD symptoms and number of traumas experienced were significantly and positively related with PTG, and PTSD symptoms were positively correlated with number of traumas experienced. Also, the results from a multiple regression analysis revealed that the intrusion, optimism, and number of traumas experienced contributed to PTG, but avoidance and hyperarousal were independent of PTG in both samples. This finding suggests that mental health practitioners could consider intrusion as not only pathology but also as one of the factors contributing to PTG in both U.S. and Japanese college students.