Abstract: Objective:To explore the application value of the level of arterial blood lactate in the evaluation of disease severity and prognosis of neonatal asphyxia.Methods:The levels of Neonatal Critical Illness Score(NCIS) and arteral blood lactate in 108 neonates with asphyxia were investigated after admission.The correlation between the score of NCIS and level of arteral blood lactate was analyzed,and the linear regression equation of which was established.The relationship between the level of arteral blood lactate and prognosis of neonatal asphyxia was observed.Results:The linear correlation analysis results showed that the lower the score was,the higher the level of arterial blood lactate was,and the relation of which was significantly negative(P<0.01).The linear regression equation showed that the concentration of arteral blood lactate was 19.403-0.177×NCIS.When the arteral blood lactate concentration was less than 3.473 mmol/L,3.473 to 7.013 mmol/L and more than 7.013 mmol/L,the incidences of severe asphyxia was 12.00%,71.93% and 100.00%,respectively,the incidences of the multiple organ injury was 0.00%,84.21% and 100.00%,respectively,and the incidences of mortality was 0.00%,1.75% and 19.23%,respectively,the differences of whose were statistically significant(P<0.01).Conclusions:The level of arterial blood lactate is a objective,sensitive and simple quantitative indicator,which can provide the reliable basis in quick and timely judging the disease severity and prognosis of neonatal asphyxia.