BACKGROUND: Regular exercise activities affect blood cells. OBJECTIVE: The purpose of this study was to evaluate the seasonal evaluation of some hematological and biochemical parameters of the Olympic Greco-Roman wrestlers. METHODS: A total of three measurements were performed on wrestlers: immediately before the training period, three months and six months after the training session. Hematological and biochemical parameters were analyzed by taking sufficient blood samples from the athletes before and after exercise. RESULTS: The total leukocyte, lymphocyte, and neutrophil values were found to be significantly higher (p< 0.05) in all three measures (beginning, 3rd and 6th months) in comparison with the values before exercise. When biochemical analyses were examined, blood glucose levels were significantly decreased after exercise in all three measures compared to before exercise. Post-exercise HDL cholesterol concentrations significantly increased (p< 0.05) while LDL cholesterol concentrations significantly decreased (p< 0.05). CONCLUSION: On all three measures fatigue exercise has significantly increased the total leukocyte, lymphocyte and neutrophil values of wrestlers, while other, hematological parameters were not affected evenly. Fatigue exercise also significantly reduced blood glucose levels and LDL cholesterol concentrations, while HDL cholesterol concentrations were increased. The six-month period training did not have a significant effect on both hematologic and biochemical parameters in all three measurements.