This article investigates the value of early diagnosis and prognostic evaluation of Doppler ultrasound for neonatal hypoxic-ischemic encephalopathy (HIE). Study population included 40 term neonates with HIE and 30 healthy controls. Color Doppler ultrasound was performed at the bedside within 24 h after birth. The transducer was placed on the temporal fontanelle to detect the hemodynamic parameters of bilateral middle cerebral arteries. The results showed that infants with HIE had significant cerebral hemodynamic disturbance. The cerebral blood flow velocity decreased or increased markedly as resistive index (RI) decreased or increased markedly, which usually suggested the diagnosis of HIE, RI < 0.50 or RI > 0.90 usually occurred in severe patients, while RI > 1.0 would be associated with later brain death. So we believe that using Pulsed Doppler ultrasound to monitor the changes of cerebral hemodynamics can be used for the early diagnosis of HIE and help us to distinguish the grades of HIE.