Abstract: Objective  To investigate the changes of serum calcium-binding protein S100β, glial fibrillary acidic protein(GFAP) and their correlation with behavioral neurotest neonatal behavioral neurological assessment(NBNA) scores in postnatal asphyxia neonates of different degrees, and to find the basis for early prediction of neonatal brain injury. 
Methods  A total of 38 cases of mild asphyxia, 16 cases of severe asphyxia and 46 cases of normal asphyxia were selected. The samples of the three groups of newborns were collected within 4 hours after birth, and serum GFAP and S100β concentrations were detected by enzyme-linked immunosorbent assay. All asphyxiated newborns underwent cranial imaging examination three to four days after admission and received Neonatal Behavioral Neurological Assessment(NBNA) score three days after birth. 
Results  The S100β level in mild asphyxia group and severe asphyxia group was significantly higher than that in control group, the difference was statistically significant(P＜0.05).There was no statistically significant difference in GFAP level among three groups(P＞0.05). The S100β level in the brain injury group was significantly higher than that in non-brain injury group, the difference was statistically significant(P＜0.05), and there was no statistically significant difference in GFAP level between two groups(P＞0.05). Spearman correlation analysis showed that Neonatal S100β level was negatively correlated with NBNA score(P＜0.05), the GFAP level was not correlated with NBNA score(P＞0.05). Regression analysis showed that S100β was the influencing factor of neonatal brain injury(P＜0.05). The AUC of the ROC curve of S100β for predicting the brain injury after asphyxia was 0.755, with sensitivity of 77.8% and specificity of 77.8%. The AUC of the ROC curve of GFAP for predicting the brain injury after asphyxia was 0.488, with sensitivity of 16.7% and specificity of 97.2%. 
Conclusion  S100β detection within 4 hours of birth is helpful for the diagnosis of neonatal asphyxia and brain injury after asphyxia, and the accuracy of predicting asphyxia brain injury is high. GFAP detection within 4 hours after birth has high specificity, but low sensitivity and accuracy.It has little reference value for the diagnosis of neonatal asphyxia and brain injury after asphyxia. It is not recommended to detect alone within 4 hours after birth. 

Key words: asphyxia neonatorum, brain injuries, S100 proteins, glial fibrillary acidic protein