Abstract: Objective　To explore the correlation between the fluctuation of blood glucose levels and brain damage in neonates with hypoglycemia. Methods　The clinical data of 58 cases of neonatal hypoglycemia diagnosed from September 2013 to August 2016 were analyzed retrospectively. According to the results of neonatal cranial MRI and/or amplitude integrated electroencephalogram (aEEG), the neonates were divided into brain injury group and non-brain injury group. The fluctuation index of blood glucose was compared between two groups, and the correlation between the fluctuation of blood glucose level and brain injury was analyzed. Results　In these 58 cases, 13 cases were in brain injury group (8 males and 5 females) and 45 cases were in non-brain injury group (27 males and 18 females). The lowest blood glucose (LBG) value in brain injury group was lower than that in non-brain injury group, while the duration of hypoglycemia, maximum blood glucose fluctuations (LAGE), standard deviation of blood glucose (SDBG), and average blood glucose fluctuations (MAGE) were higher than those in non-brain injury group, and they were all significantly different (P all<0.001). Conclusions　Whether the hypoglycemia in newborn could lead to the brain injury or not depends not only on the minimum hypoglycaemia level and duration of hypoglycemia, but also on the indicators of glucose variation, such as LAGE, SDBG and MAGE.