Objective To explore the effect of perinatal asphyxia on levels of blood biochemical parameters and brain CT imaging findings in infants of different gestational age. Methods The clinical data of 68 infants treated in NICU of our hospital because of perinatal asphyxia during the period from March 2015 to March 2017 were retrospectively analyzed. According to the degree of asphyxia, the infants were divided into the severe asphyxia group (32 cases, including 18 term infants and 14 premature infants) and the mild asphyxia group (36 cases, including 21 term infants and 15 premature infants). 33 healthy infants were selected as the control group (17 term infants and 16 premature infants). The neonatal venous blood of three groups was collected to determine concentrations of serum aspartate aminotransferase (AST), α-hydroxybutyrate dehydrogenase (α-HBDH) and insulin-like growth factor (IGF-1), and levels of above-mentioned biochemical indexes were compared. All infants were examined with brain CT and images were analyzed. Results Levels of serum AST and α-HBDH in term infants showed the severe asphyxia group > the mild asphyxia group > the control group (P<0.05). The levels in premature infants in the severe asphyxia and the mild asphyxia group were higher than those in the control group (P<0.05). Serum IGF-1 levels in term infants and premature infants showed the severe asphyxia group < the mild asphyxia group < the control group (P<0.05). The brain CT images of infants with asphyxia showed different degrees of low-density foci of brain parenchyma, and some of them were complicated with hemorrhagic foci. Conclusion There ere obvious differences in levels of serum biochemical parameters and brain CT imaging findings in infants of different gestational age and with different degrees of asphyxia. They can be used as effective indexes for diagnosis of neonatal asphyxia.