Introduction: This prospective observational study evaluated the hemodynamic changes in cardiac function and cerebral blood flow velocity (CBFV) in neonates with hypoxic-ischemic encephalopathy (HIE) requiring therapeutic hypothermia (TH). Methods: Data were collected at five timepoints: pre-TH (T0), 0-24h of TH (T1), 24-48h of TH (T2), 48-72h of TH (T3), and within 24h post-rewarming (T4). Healthy neonates served as the control group (n=20). Results: A total of 43 HIE neonates requiring TH were enrolled. The Left Ventricular Output was significantly lower compared to the control group at T1 and T2, and increasing from T1 to T4 (92.8±29.5 ml/kg.min vs 103±29.7 ml/kg.min vs 109.5±28 ml/ kg.min vs 144.5±34.4* ml/kg.min (T4 vs T1, T2 or T3: p