The article substantiates the features of leadership in the professional activity of a teacher. It is emphasized that leadership is a specific type of management relationship, which is based on social interaction, and the leader in this situation is an innovator. The functional differences of a leadership (regulation of interpersonal relations in the team, spontaneity) and management (organization of official relations of the group as a certain social organization, purposefulness, control of various elements of social structure) are determined. It is argued that a person's leadership qualities mean a set of their psychological qualities, abilities and features of intragroup interaction that ensure the success of their leadership functions. Important leadership behavioral qualities of a leader: responsibility, cooperation, personal development, resilience, awareness, integrity. The organizational and managerial qualities of a teacher-leader (professional competence, moral qualities, ability to work, culture of taking into account different points of view, etc.) are systematized and the differences in the activity of a teacher-functionary and a teacher-leader are determined. It is noted that the effectiveness of leadership is determined by the teacherʼs ability to perceive and satisfy the specific needs of the group at each stage and choose the appropriate style of influence, harmoniously combining individual and group needs while providing the necessary conditions for completing the assignment. The main problem of leadership is to maintain consensus and unity of the staff of the educational organization on the basis of common goals and values, the implementation of a specific approach to reveal the individual potential of staff. It is concluded that the training of a teacher-leader should be aimed at developing his analytical skills, at the formation of design and modeling competencies, at stimulating the individual to a possible solution of the problems in difficult and uncertain situations, at the ability to respond not only quickly but also on the basis of various strategies behavior. Keywords: leadership, teacher, qualities of a leader, professional competence.