In neonatal hypoxo-ischemic encephalopathy (HIE), therapeutic hypothermia is nowadays the only effective neuroprotective mean in order to decrease second state lesions within 6h after anoxo-ischemia. Hypothermia has a positive effect on mortality and morbidity rates as well as on seizures. Conventional EEG (cEEG) is an important tool for early neonatal cerebral function evaluation before deciding hypothermia. EEG monitoring during 72h hypothermia and after rewarming is also crucial for prognosis.Precise retrospectively cEEG comparatively to aEEG in hypothermia decision and determine prognosis on cEEG monitoring with at least 2years follow-up.75 neonates 36–41 GA Wks, in the university hospital in Lille with anoxo-ischemia were included; In our clinical practice hypothermia was decided on Grade 2 and 3 EEG abnormalities according to French classification.1/cEEG done within the 6 first hours of life was compared retrospectively to aEEG in hypothermia making decision.2/cEEG monitoring done during 72h hypothermia and rewarming was compared to clinical evaluation at two years of age to determine EEG prognosis value.50% of newborn with HIE received hypothermia. False negative and positive indications of hypothermia were found on aEEG conversely to cEEG. Prognosis value was good in Grade 2 and 3 EEG. In grade 2 correlation was good in most cases.cEEG remains the gold standard for decision-making of hypothermia.We demonstrate the need to better clarify grade 2 abnormalities in order to improve prognosis evaluation; specially background and EEG pattern morphology.