<p>This study introduces the Traumatized Narrative Identity Scale (TNIS), a novel tool designed to assess the impact of Stressful Life Events (SLEs) on narrative identity among individuals. Traumatized narrative identity is conceptualized as the extent to which individuals perceive their self-narratives as fragmented, confused, and powerless due to past traumatic experiences. The TNIS focuses on three critical processes—meaning-making, unity, and purpose—disrupted by SLEs, which can hinder individuals’ ability to integrate these events into a coherent life story. Psychometric evaluation of the TNIS was conducted with a sample of 438 Iranian adults, employing exploratory and confirmatory factor analyses to establish validity. The results indicate that the TNIS functions as a single-factor model, demonstrating strong evidence of internal structure, evidence of associations to other variables, and acceptable reliability of the scores of the measure. This scale may enhance understanding of how trauma influences narrative identity and servs as a resource for clinicians in therapeutic settings, facilitating more effective interventions aimed at narrative identity reconstruction.</p>