High-quality mentoring relationship and relational energy (RE) developed during the interaction between leaders and subordinates are major determinants of desirable employees work outcomes. There are two unanswered questions about relationships involving these variables, how do different leadership styles affect relational energy and quality of mentoring relationship? What role does relational energy play in the relationship between leadership styles and high-quality mentoring relationship? Cross-sectional study involving 210 participants from 4 organizations in Nigeria, indicate that servant leadership is related to RE and quality of mentoring relationship, while autocratic and transactional leadership styles are not related to any of the variables. The results also confirm the critical position of RE in the development of high quality mentoring relationship.