The present study was conducted to compare the MMPI profile of 29 Posttraumatic StressDisorder patients with 25 Organic Brain Affective or Personality Disoder patiene who were admitted to Ewha Womans University Hospital from March to August of 1995. MMPI-R(Minnesota Multiphasic Personality Inventory), consisted of 556 items and of the revised standard form, was administered to the subjects. No significant difference was found between thetwo groups in age, sex, and education level.

Results of the present study were as follows :

1) Two subgroups were formed as a result of multivariate cluster analysis of T scores of allMMPI scales from the Posttraumatic Stress Disorder group. The first sub-group (N=22) showed moderate high socre on 3-1-2, 7-8 scales. The second sub-group (N=7) presented severehigh score on F validity scale and all clinical scale exept 5 scale so the t scores of 8-6-7,1-2-3-4scales were within 65-80.

2) Two subgroups were formed as a result of multivariate cluster analysis of T scores of allMMPI scales from the Organic Brain Affective or Personality Disorder group. The first subgroup (N=8) gave mild high score on K scale and on no clinical scales. The second sub-group(N=17) presented moderate high score on F scale and on 1,2,3,6,7,8 scales.

3) Exept for the defensive groups, it was found that F,6 scales and 3 scale were useful to differntiate the Posttraumatic Stress Disoders from the Organic Brain Affective or Personality Disorders.

4) The results suggest that MMPI is useful to differentiate the Posttraumatic Stress Disodersfrom the Organic Brain Affective or Personality Disorders.