The paper presents the influence of the transactional and transformational leadership style on the loyalty of employees in the organization. At the beginning, the concept of leadership and leader, its role, abilities and styles are defined. This is followed by a chapter in which leadership is elaborated by elements and dimensions and the relationship between leadership and management, and ends with a historical overview and leadership theories, where leadership styles according to different leadership theories, such as the theory based on the characteristics of leaders, the theory based on the behavior of leaders and situational theories, are specially discussed leadership. The fourth chapter refers to the dominant styles in contemporary business, i.e. transactional and transformational leadership and their comparison. The next chapter defines the concept of loyalty to the organization, explains affective, instrumental and normative loyalty and the management of loyalty to the organization, i.e. what is the role of top management and human resources management in managing loyalty to the organization. The following is an overview of the positive and negative consequences of loyalty to the organization and the challenges in fostering loyalty associated with changes in the work environment and the connection between transformational leadership and loyalty to the organization. The work ends with the implementation of a survey questionnaire and responds to the set goals and hypotheses, and whether the hypotheses are confirmed or refuted is explained in the conclusion of the work.