Toxic leadership has become the focus of attention in recent years for many organizations. In general terms, toxic leadership refers to leader behaviors leading to negative outcomes. Toxic leadership can result in decreasing personnel efficiency and adversely affecting cost-benefit relationship for organizations. Simultaneously, this concept is alleged to cause high rates of absenteeism, increasing personnel transfer, poor performance and groupthink. Despite the growing interest in the world of science, it is observed that systematic, scientific field works on toxic leadership are inadequate. Lack of fieldwork data can be considered as an important challenge to define the concept of toxic leadership properly.