Background: Workplace bullying has an influence on everyone in the organization, including the patient's health and the entire workplace. Psychological capital described as a favorable mental state linked to nurses' mental health, the standard of their treatment, and patient outcomes. The Aim of this study was to assess relation between workplace bullying and psychological capital among nurses. Subjects and Method: Cross-sectional design was used in this study. Setting: The study was conducted at Al- Ahrar Zagzag Teaching Hospital in Zagazig-AL-sharqia, Egypt.  Subjects: A purposive sample of 120 nurses working in the previous mentioned setting. Tools: Data were collected using two tools, Tool (I): Work Place Bullying Scale. Tool (II): Psychological Capital Scale. Results: the result of study indicated that 95% of nurses not exposed to workplace bullying, and 72.5% of studied nurses had psychological capital moderately. There was non- significant relationship between characteristics of the studied nurses and their psychological capital. There was a highly statistical significant negative correlation between domains of workplace bullying and domains of psychological capital (p<0.01).  Conclusion: Majority of the nurses had low level of workplace bullying; nearly three quarter of studied nurses had psychological capital moderately. There was a statistically significant negative correlation between workplace bullying and psychological capital. Workplace bullying and age were significant negative predictors of psychological capital among the studied nurses.  Recommendations: Conducting training program for staff nurses about bullying, Intervention programs are recommended for nurses to enhance their level of psychological capital.