Background: Success in the workplace and at the staff level depends on the interpersonal and developmental
interaction known as mentoring between head nurses and their staff nurses. A mentoring relationship consists of regular
meetings when both parties exchange ideas, discuss progress, and set goals for continued development and
organizational performance. It is based on mutual trust, respect, and communication. Aim: To assess head nurses'
mentoring function and its relation with organizational effectiveness at Oncology Center Mansoura University. Method:
The study, which included 282 staff nurses from the Oncology Center, used a descriptive correlational approach through
the use of the Organizational Effectiveness Questionnaire and the Head Nurses' Mentoring on Staff Nurses Scale.
Results: The majority of staff nurses were satisfied with their head nurses' mentoring function. Most of them had high
level of perception regarding their organizational effectiveness. There was a highly statistically significant positive
correlation between total mentoring function and total organizational effectiveness. Conclusion: We can improve
organizational effectiveness through increasing head nurses' mentoring function. Recommendations: Encouraging head
nurses to participate in continuing education programs to continually updating their knowledge and skills related to
mentoring function. Maintaining environment that encourage head nurses to provide mentoring function to their staff
nurses and showing recognition and appreciation for head nurses for their effort in mentoring their staff nurses.