The aims of the present research are to test the effects of running and playing exercises on leucocyte and differential leucocyte accounts, and to test the possible differences between running and playing exercises in terms of leucocyte accounts. They were thirty two male young soccer players. Participants arrived at the laboratory after a 12-hour fast. Blood samples were collected from an indwelling heparin locked latex venous catheter before and after training protocol. Differential leukocyte counts were performed on K3EDTA-treated blood, using an automated Coulter JT hematology analyzer. Neutrophil, lymphocyte, monocyte and total leucocyte accounts were increased after acute exercise compared to before in playing group. All leucocyte parameters except lymphocyte account were increased after acute exercise compared to before in running group. The differences between two groups were not significant before and after exercise for all parameters except lymphocyte account. It can be stated that acute vigorous exercise in running or playing training results in extremely physical stress. Playing or running do not differs in terms of stress. [Note: The volume number (10) displayed on this PDF is incorrect. The correct volume number is 11.]