Background: Traumatic Head Injury (THI) is a disruption in the normal function of the brain that caused by a blow or jolt to the head. The role of critical care nurses is a vital at the acute care by giving priority of the immediate assessment, stabilization of the airway and circulation and prevention of secondary injury. The aim of this study was to evaluate the effect of an educational program on the nurses' performance and health outcomes for patients with traumatic head injury. Study design: A quasi-experimental design was used. Settings: This study was conducted in the emergency unit and the emergency intensive care unit at Banha University Hospital. Subject: A convenient sample of (50) registered nurses caring for patients with THI and (50) patients with THI were included in the study. Tools: Three tools were used for data collection; I-self-administered questionnaire tool, II-the nurses' practice observational checklist and III-patients' health outcomes assessment. Results: All of the nurses had unsatisfactory knowledge and practice regarding caring for patients with THI pre-program implementation which improved immediately post program implementation (30% and 24%), respectively. The mean of the studied patients regarding total trauma scale pre-program implementation was 16.89  10.61 that improved immediately post program implementation 13.24  12.08. Conclusion: There was a highly statistical significant improvement in the level of nurses' performance and health outcomes for patients with THI after implementation of the educational program. Recommendations: The importance of continuous in-service training programs about THI for refreshing and updating the nurses' knowledge and practice regarding THI.