Abstract In Iran, spirituality is one of the most critical factors affecting veterans' health. The present study aimed to determine the mediating role of ego resilience in the relationship between spirituality and trait gratitude with post-traumatic growth in Iranian veterans with PTSD. In the present descriptive and correlational study, 300 veterans with PTSD were hospitalized and treated at Isar Psychiatric Hospital in Ardabil in 2021 and were selected as the sample. Data were collected using Tedeschi and Calhoun's Traumatic Developmental Questionnaire, Parsian and Dunning, Mc Cullough et al.'s Trait Gratitude Questionnaire, and Block et al.'s Ego Resilience Questionnaire. Based on the obtained results and various fit indices, the direct and indirect relationships between spirituality, trait gratitude, ego resilience, and post-traumatic growth in veterans with post-traumatic stress disorder were confirmed (p < 0.01). Also, spirituality and trait gratitude through ego resilience indirectly affected the post-traumatic growth of veterans with PTSD (P < 0.05). Thus, targeting these three components through psychological therapies may effectively increase post-traumatic growth in veterans experiencing trauma.
