The purpose of this study was to investigate the psychometric properties of the Covid-19 traumatic stress scale Which examines the effects of the corona virus on various aspects of Iranian life. Method: The present study was a descriptive correlational study. The statistical population included all adults in Tehran in the age range of 17 to 72 years. 461 people participated in the study through an online call. To analyze the data, Classical Test Theory and Item Response Theory were used and statistical software Spss version 26 and R software version 4.0.1 were used. Results: The results of the instrument validity study using exploratory and confirmatory factor analysis (classical theory) and multidimensional models (Item Response Theory) confirmed three factors related to the Covid-19 traumatic stress Scale. convergent and divergent validity of the instrument was also confirmed. The validity of the scale was confirmed by Cronbach's alpha method (alpha values above 0.70 for all three factors and the total score) and the retest method (high intra-class correlation between the two measurement steps) in the classical approach of the test. Based Item Response Theory, the validity of the data was assessed using the Information function and measurement error. The Information function showed that all three factors in the trait level range between 2-to 2 had the highest awareness and the least measurement error (p <0.05). Conclusion: The Covid-19 traumatic stress scale has good validity and reliability in Iranian society and can be used as a valid scientific tool to assess the effects of the Corona virus on various aspects of Iranian life.