Background: Servant Leadership in nursing is closely related to the ability to influence nurse teams and hospital patients. Servant leadership is defined as “excessive service to others, a holistic approach to work, fostering a feeling of togetherness, and the sharing of authority in decision-making”. Aim of the study: the study aimed to assess the effect of servant leadership training program on sustainable development behavior of head nurses. Subjects and Methods: Research design: A quasiexperimental research design was utilized in this study. Setting: The study was conducted at Zagazig University Hospitals, which include two sectors the Emergency sector and El-Salam sector Subjects: Convenience sample, All head nurses (n=100) who working in the above mentioned setting and they were divided randomly into two equal groups; study group and control group. Tools of data collection three tools were used for data collection (1) knowledge questionnaire test, which included head nurses' personal data and head nurses' knowledge test regarding Servant leadership (2) Servant leadership skills questionnaire. (3) Sustainable development behavior scale Results: There was a statistically significant difference in head nurses' knowledge and skills pre, post and follow up after applying Servant leadership training program. There was statistically significant relation between head nurses' knowledge and skills regarding Servant leadership and sustainable development behavior. Conclusion: The training program for head nurses was effective and improved their level of knowledge and skills also there was statistically significant relation between head nurses' knowledge and skills regarding Servant leadership and sustainable development behavior. Recommendations: A Servant leadership educational program is recommended to be recognized and implemented for all head nurses who in a management position in the nursing field in other hospitals. Hospital and nursing administrators should do their best for keeping and enhancing nurses' sustainable development behavior