Attention to the diversity of human resources, including the difference of generations, is necessary to achieve an appropriate environment for the development of employees. So, special attention should paid to generational relations and related human resource strategies. In this way, the subject of this chapter in the first stage is to introduce generations and to identify the differences that are observed in the behavioral characteristics of individuals of each generation. In the second stage, considering the presence of different generations of workforces in organizations, it is examined whether generational differences have a significant effect on organizational behavior variables in organizations, and if so, how and how much this impact will be.