Background: Authentic leadership focuses on fairness and transparency to the staff, encourages open sharing of information, accepts nurses' inputs, and empowers them to be clear in developing their expertise and mastery which can have a positive influence on nurses' self-efficacy. Purpose: To identify the authentic leadership and its relation to nurses' self-efficacy. Method: Study design: A descriptive correlational design was utilized. Setting: The study was conducted in Ashmoun General Hospital in Ashmoun city at Menoufia Governorate. Study sample:  It included two study groups. The first group was all nurse managers (75). The second group involved a simple random sample of 182 staff nurses from total number of 335 staff nurses. Data collection instruments: Two instruments were used to collect the data.   Instrument 1: Authentic Leadership Questionnaire and instrument 2: General Self-Efficacy Scale. Results: Authentic leadership level was high from the studied nurse managers' perspective. While authentic leadership level was moderate from the studied staff nurses' perspective. The internalized moral perspective dimension had the highest percent score and the first rank among authentic leadership dimensions as perceived by the two study groups. Nurses' self-efficacy level was moderate among the studied staff nurses. Conclusion: There was a highly statistically significant positive correlation between all dimensions of authentic leadership and self-efficacy from the studied staff nurses' perspective. Recommendations: Establishing evidence-based research findings regarding effective leadership styles in practice. Conducting educational workshops for under and newly-graduated nurses in order to train them on improving self-efficacy and leadership skills.