Background: Patient safety has become a top issue in the global health-care quality agenda. Aim: The study aimed to explore the impact of safety guidelines on nurses' knowledge regarding incidents and nurses' safety attitude at Neonatal Intensive Care Unit. Subject & Methods: A quasi-experimental research design was used to conduct the study at three capital neonatal intensive care units. Thirty-three nurses were recruited for this study using purposive sampling technique. Data were collected using: (I) Safety Attitudes Questionnaire, (II) Incident sheet, and (III) Nurses' safety knowledge questionnaire /pre and posttest. Results: According to the study's findings, 69.3 % of nurses indicated a positive attitude toward the teamwork climate and 35.1 % of the most common incidents recorded were invasive procedure. In addition, there was highly statistical significant difference in the nurses' total knowledge before and after the educational guidelines intervention. Conclusion: This study concluded that, a low positive attitude in most areas toward safety was reported by the nurses. As well, the most incidents reported were invasive procedures and respiratory care errors resulted in minor problems. The guidelines program intervention was effective for improving nurses' knowledge bout neonatal safety measures. Implications for clinical practices: Nurse practitioners should apply incident reporting systems that are a key strategy to learn from incidents and monitor progress in the prevention of medical errors recurrence. It is necessary to train neonatal nurses and supervisors in relation patient safety competency.