Abstract： Objective To investigate the value of early quantified analysis of perinatal white matter injury by cranial ultrasound gray scale measurement. Methods The cranial ultrasound exam was performed in 152 newborns with different gestational age0 early after their birth. These newborns were divided into two groups: 104 newborns diagnosed as white matter injury within 7 days after birth were taken as patient group; while 48 newborns who were not were taken as control group. The gray scale values in the trigone of lateral ventricle of white matter were analyzed by medical image analysis system. The newborns in patient group accepted cranial ultrasound exam at one month after birth, the grey scale value and cyst in the white matter were recorded. Three to six months old, the cranial ultrasound exam was repeated to record the change of white matter volume, morphology of lateral ventricle and change of the cysts. When they were 1.5 to 2 years old, the neurological function were quantitatively evaluated with Gesell score, and the results were classified as normal and abnormal.The relationships between gray scale value and neuro-developmental outcome were analyzed with receiver operating characteristic curve.Results During neonatal period, the average gray scale values in severely injured group was 131.72±2.40, higher than that of mildly injured group (116.61±2.48), and which in mildly injury group was higher than that in control group (100.50±1.66) (q=4. 521 and 4. 492, P＜0. 05). It was showed by receiver operating characteristic curve that gray scale value ＞114.37 could help to diagnose white matter injury, with the sensitivity of 0. 721 and the specificity of 0. 854; gray scale value ＞119.80 could help to diagnose severe white matter injury,with the sensitivity of 0. 716 and the specificity of 0. 776. As the gray scale value increased, the incidence of white matter volume decreased and the enlargement of lateral ventricle in the later period of injury increased. Patients with gray scale value ＞ 130 tended to suffer from leucomalacia. During neonatal period, the incidence of abnormal neurodevelopment before 2 years old was 5.0％ in patients with gray scale value ＜ 110, while it was 27.8 ％ in the patients with gray scale value between 110 and 120, 47.8％ in the patients with gray scale value ＞ 120.Conclusions Quantified analysis of ultrasound gray scale value might be promising in early diagnosis of perinatal white matter injury through early judgement of the outcomes of white matter injury and forward neurodevelopment.