Background: Acts to protect the safety of others, attempting to prevent the development of accidents, and proactively seeking to improve organizational safety procedures and general workplace safety conditions were all examples of safety citizenship behavior. Aim: To examine the relation between leaders' emotional intelligence, leaders' and nurses' safety citizenship role definitions and behavior, self- efficacy, and resilience at Zagazig University Hospitals. Sample: A convenience sample of all available head nurses (200), in addition to a systematic random sample of 400 staff nurses. Setting: The study was conducted at Zagazig University Hospitals Tools of data collection: Head nurses questionnaire sheet: composed of three parts; personal and job characteristics of head nurses, leaders' emotional intelligence scale, and leaders' safety citizenship role definitions and behavior scale. As well, staff nurses' questionnaire sheet: composed of four parts; personal and job characteristics of staff nurses, safety citizenship role definitions and behavior scale, general self-efficacy scale, and resiliency scale. Results: Leaders' emotional intelligence was significantly and positively correlated to leaders' safety citizenship role definitions and behavior, staff nurses' safety citizenship role definitions and behavior, self-efficacy, and resilience. Conclusion: Self- efficacy is a partial mediator in the relationship between leaders` emotional intelligence and safety citizenship role definitions and behavior from both leaders and nurses. In addition, resilience is a full mediator in the relationship between leaders' emotional intelligence and safety citizenship role definitions and behavior from both leaders and staff nurses. Recommendations: Provide a training program for both staff nurses and nurse managers about safety citizenship role definitions and behavior and encourage them to apply it, to improve their organization’s safety performance.