This study was aimed to explore whether hyperglycemia during chemotherapy influences the prognosis of children with acute lymphocytic leukemia (ALL). The clinical medical records of all newly diagnosed patients with ALL at SUN Yat-Sen Memorial Hospital from June 2008 to May 2012 were analyzed retrospectively. The median time of follow-up for patients was 2.6 years (range 0.08 to 4.9 years). Patients were divided to hyperglycemia and euglycemia groups according to their blood glucose concentrations during chemotherapy which contains L-asp and dexamethasone. The variables between two groups were compared using χ(2) test, the RFS and OS among two groups were compared by use of Kaplan-Meier and Cox-proportional hazard analyses. The results showed that the hyperglycemia correlated with older age (43.33% vs 19.23%, P = 0.008) and high-risk disease at diagnosis (26.62% vs 4.76%, P = 0.017) , but did not associate with sex (P = 0.059). Patients with hyperglycemia had worse OS (94.2 ± 2.9% vs 83.1 ± 6.3%, P = 0.014) and more poor RFS (64.1 ± 8.9% vs 88.6 ± 3.8%, P < 0.001) at 5 years than their counterpart. It is concluded that the incidence rate of hyperglycemia during chemotherapy correlated with older age and high-risk disease in ALL children, and the patients with hyperglycemia during chemotherapy may have poorer prognosis.