Objectives : The aim of this study was to investigate clinical meaning of hallucination among patients with posttraumatic stress disorder (PTSD). Methods : PTSD patients with hallucination (n=50) were selected and matched with the PTSD patients without hallucination (n=50) by age and sex. The patients were evaluated in two different aspects, pathologic aspects which can develop after traumatic event, and positive/adaptive aspects which are concerned in positive psychology. In addition to these, temperament and character features between two groups were also evaluated using the Temperament and Character Inventory (TCI). Results : Except for the total score of DES (Dissociative Experience Scale) and the score of re-experience subscale of CAPS (Clinician Administered PTSD Scale), clinical characteristics did not show any significant difference between the two groups. Among the comparison of seven higher dimensions in TCI profiles, only Self-transcendence showed significant difference between the two groups. Conclusion : The two groups did not show significant differences in pathologic aspects except for factors that may contribute to development of hallucination. Furthermore, authors could not find any differences in positive/adaptive aspects.