Perinatal asphyxia leading to Hypoxic Ischemic Encephalopathy (HIE) is a major concern in newborn morbidity and mortality in India. In this study we have done transcranial USG and MRI brain of both term and preterm newborns to detect the HIE related changes in neonatal brain and also evaluated wheather MRI is better than USG in detecting the lesions.This cross sectional analytical study was conducted at Calcutta National Medical College and Hospital, Kolkata with 57 newborns (26 preterm,31 term) for a period of one year. Cranial USG was done on day 5 to day 7 of the baby and MRI brain of the same baby after 24 hrs of doing USG. We found that cerebral oedema, lesions of basal Ganglia, thalamus and parasagittal subcortical white matter injury were more common in term babies, whereas Germinal Matrix Haemorrage (GMH), IntraVentricular Haemorrage (IVH) and PeriVentricular Leucomalacia (PVL) were common in preterms.When we compared USG and MRI findings we found statistically significant difference in relation to detection of abnormal findings(49 by MRI,33 by USG},deep grey matter insult of basal ganglia, thalamus (22 by MRI, 8 by USG), parasagittal subcortical white matter injury (6 by MRI,0 by USG) with p value less than 0.05.Detection of GMH and IVH was 15 by MRI and 9 by USG. In conclusion, though USG is a less expensive initial screening tool in detecting HIE related lesions and it can detect IVH, GMH very effectively, but MRI brain should be the final investigation of choice to detect both central and peripheral cortical injuries in newborn with perinatal asphyxia.