Background: Antenatal inflammation is associated with the increasingly severe and negative neurological findings of neonatal ecephalopathy. A reduction in antenatal inflammation reduces neurological damage. The effect of therapeutic hypothermia on inflammation is not clear and remains the subject of research. Aim: The aim of this study was to investigate the inflammatory cell response in neonatal ecephalopathy cases treated with therapeutic hypothermia. Methods: The study included a total of 102 cases, 51 cases diagnosed with perinatal asphyxia and a control group of 51 healthy newborns. Blood samples were taken before therapeutic hypothermia treatment and at the 24th and 72th hours of treatment in patients with perinatal asphyxia. In the control group, blood samples were taken in the first 6 hours postnatally. Results: In the asphytic group, mean leukocyte (p<0.001), neutrophil (p<0.001), and lymphocyte (p=0. 014) values within the first 6 hours were significantly higher than those of the control group. The specificity for leukocyte, neutrophil and lymphocyte (measured before TH) was 80.4%, 88.2% and 60.8%, and sensitivity was 84.3%, 88.2% and 62.7%, respectively. The mean leukocyte, thrombocyte, and neutrophil values during the first 6 hours after delivery were significantly higher than the mean values at the 24th and 72nd hours after TH (p<0.001), and the mean platelet volume values were significantly lower (p<0.001). Conclusion: High leukocyte, neutrophil and lymphocyte values and low thrombocyte count in the first 6 hours of life may be an early sign of perinatal asphyxia and can be used as a marker to start treatment. It is thought that by decreasing the number of inflammatory cells, therapeutic hypothermia reduces the severity of encephalopathy and potentially negative results.