Rating scales for post traumatic stress disorder (PTSD) should be consistents with DSM IV criteria, and should be validate for each culture.To validate a PTSD checklist in a Colombian little town population, which was semi destructed by a guerrilla attack.A stratified, representative and randomized sample of 202 adult participants, aged over 15 year old, was selected from San Joaquin (Santander Colombia) two year after an guerrilla attack. A structured interview (SCID I), based on DSM IV criteria, was developed with each member of the sample. 76 participants (37.6%) met criteria for PTSD, and 126 (62.4%) were classified as non PTSD. A rating checklist with 24 symptoms of PTSD was applied by self report. Each item of the scale was scored 1 to 4.PTSD checklist had a reliability Cronbach s alpha coefficient of 0.97. PTSD group scored 70.4 22.9, and non PTSD 37.2 13.7 (p< 0.0001) on the PTSD checklist. A discriminant analysis found that the scale had a correctly classification capability of 88.6% (p< 0.0001). Sensibility was found between 76.3% for a cut off point of 51 and 81.6% for cut off point of 45. Specificity changed between 71.4% for a cut off point of 45 and 84.4% for a cut off point of 51.Checklist for PTSD had a high reliability, good discriminant capability, and good sensibility and specificity.