Background: In the face of COVID-19, healthcare workers need to cope with the ongoing stressors at play and keep psychological distress at a minimum level. This study examined the psychosocial and demographic factors associated with nurse's resilience in the hospitals of Ahvaz that is one of the top cities infected with COVID-19 in Iran. Methods: The present cross-sectional study was conducted on 387 Iranian nurses in Ahvaz city. For data collection purposes, three online questionnaires (including Copenhagen Psychosocial, Demographic, and Connor-Davidson Resilience Scale) were distributed among the participants. Results: The mean resilience score was equal to 61.8 +/- 14.8 for 387 nurses. Resilience had a statistically significant negative correlation with quantitative demand (r = -0.273, P < 0.008), work pace (r = -0.262, P < 0.011), emotional demand (r = -0.226, P < 0.030), stress (r = -0.458, P < 0.000), and burnout (r = -0.287, P < 0.005). Multiple linear regression analysis indicated that stress, job satisfaction, burnout and age were the main predictors of nurses' resilience during the (COVID-19) pandemic (R-2 = 0.45). Conclusions: We identified psychosocial and demographic predictive factors that may contribute to greater resilience among nurses during the COVID-19 outbreak. The findings of this study can be used to implement psychosocial interventions to amplify the resilience of medical staff during the COVID-19 outbreak.