Objectives : Given the lack of a specialized instrument for evaluating Post-traumatic Stress Disorder (PTSD) in Iran, current study aimed to standardize the Secondary Trauma Stress Scale ( STSS) in warfare victims’ children . Method: The study population included warfare victims’ children living in Yazd, Isfahan, Najafabad, and Yasuj studying at Shahed and Isargar Schools of these cities. Among that population subjects were selected using cluster sampling method. Data was collected by STSS , Mississippi PTSD Scale, and Depression Anxiety Stress Scale (DASS-21). Confirmation factor analysis, Pearson correlation, and independent samples t-test were used to analyze the data. Results: The confirmatory factor analysis revealed that the STSS included three subscales of intrusion, avoidance and arousal and that its factor structure was similar to the original version of the scale. The Cronbach's Alpha for the whole scale was calculated as 0.89 and content validity of the scale was approved by some specialists experienced in the subject. The significantly high correlations among STSS score and scores from stress, anxiety, and depression subscales and Mississippi PTSD subscales approved convergent validity of the scale (p<0.01). Moreover, the STSS was able to discriminate the group of subjects with high mental health from those with low mental health. Conclusion: The Persian version of STSS has a favorable reliability and validity in Iranian warfare victims’ children.