Introduction: Nursing is one of the most stressful professions worldwide. Job stressors can have a substantial impact on the mental health of nurses. This study aimed to assess how much workplace stressors can predict each component of this population's mmental health Methods: 419 nurses from eight tertiary hospitals in Tehran were enrolled for this observational survey, and data was collected from a three-part questionnaire including the Depression, Anxiety, and Stress Scale-21 Items (DASS-21, Extended Nursing Stress Scale (ENSS), and demographic questions. Multivariate regression and factor analysis were performed to build a Structural equation modeling between variables Results: The Correlation between Stress, anxiety, depression, and work stressor were significant (p-value=0. 01). Based on the (SEM) model, for each component of DASS (Stress, anxiety, depression), seven items in the questionnaire were significant and internally consistent(p-value: 0. 05). In the ENSS questionnaire, all nine subscales significantly predicted the total nursing stress score. Conclusions: Females, single, and nurses with more than six years of experience scored higher on the work stress scale. The workload is the most significant stressor in depression and, as a result, poor mental health.