Background: Green management become important part of our life, as it provides benefits to patients and staff, in a larger sense, to communities near and far and to unborn generations, and with no maleficence. The aim of the study: Was to assess the effect of nursing management staff about green management program on patient safety. Research design: Quasi experimental research design was used to conduct the aim of this study. Setting: The study was conducted in the Elaraby Hospital (ICU and inpatient department) affiliated to Menoufia, Egypt. Subjects: The subjects included in study consisted of two group's namely nursing management staff (60) and patients' groups (40). Tools: Three tools were used; (1) Green management Knowledge Questionnaire, it involved the nursing staff management socio demographic characteristics, green management knowledge questionnaire (2) Green management observation checklist and (3) Patient safety assessment questionnaire. Results: There was highly statistically significant positive correlations between total knowledge and total practices of nursing management staff at pre& immediately post and follow up (after 3 months) program phase. Highly statistically significant positive correlations are found between total knowledge and total patient safety at pre& immediately post and follow up (after3months) the program. As well, there are highly statistically significant positive correlations between Total practices and Total patient safety at pre& immediately post and follow up (after 3 months) the program .Conclusion: Improving nursing management staff knowledge ,practice about green management  post program. Recommendations: Ongoing educational and training programs are needed for nursing management staff about green management and providing patient's education to improve their safety at Elaraby Hospital.