Background: A career plateau is a persistent stagnation that drives nurses to progressively feel that the organization no longer supports their career development. However, in recent years, there has also been a concentration on the ‘dark' side of leadership and how dark leaders can undermine the value of their followers. Aim: This study explored the relationship between career plateau and dark leadership in healthcare organizations from the perspective of nurses. Subjects and method: Design: A descriptive correlational research design was carried out in this study. Setting: The study was applied at the El Salam sector, one of the sectors of Zagazig University hospitals. Subjects: The study sample was a convenience sample of 274 staff nurses. Tools: two tools were utilized for data collection: Tool I: consisted of two parts: Part 1: Personal data, and Part 2: Employee Career Plateau Scale. Tool II: Dark Side Leadership Profile (DSLP). Results: The findings indicated more than half of staff nurses were non-plateaued and less than half of them were plateaued while more than three-fifths of the studied nurses perceived a moderate level of dark side leadership, about one-quarter of them perceived a high tendency to dark traits, while less than one fifth perceived low tendency to dark traits. Conclusion: The analysis revealed a significant negative correlation between head nurses' dark leadership and nurses' career plateau. Recommendations: It is necessary to supply nursing staff with strategic education programs about their job description and road map for managing their achievements. More research is recommended.