This study implemented a randomized crossover design to evaluate the efficacy and safety of switching from insulin glargine (IGlar) to insulin degludec (IDeg) in 18 children (11 males, 7 females; age 11.0 ± 0.5 years) with type 1 diabetes. All subjects had previously used IGlar once daily at bedtime. We compared fasting plasma glucose (FPG) and HbA1c levels, frequencies of overall and nocturnal (2200 h - 0659 h) hypoglycemia, and basal insulin dose at the baseline with those measured during a 24-week period during which IGlar or IDeg was administered in combination with pre-meal rapid acting insulin analogues. IDeg was initially given at the same dose as IGlar but was subsequently titrated to achieve FPG levels of 90-140 mg/dL. There were no significant changes in FPG and HbA1c levels from the baseline during the 24-week study period with IGlar or IDeg. The daily basal insulin dose did not significantly differ with IGlar or IDeg. Although the frequencies of overall hypoglycemia were similar, nocturnal hypoglycemia significantly decreased at 12 and 24 weeks from the baseline with IDeg use (2 ± 0.4 vs. 0 ± 0.3, 0 ± 0.5 episodes/month, both P <0.05), whereas no significant change in the frequency of nocturnal hypoglycemia was observed with IGlar. No severe hypoglycemia occurred during the study period with either basal insulin analogues. These results suggest that IDeg, injected once at bedtime, may provide similar glycemic control as IGlar while better reducing the risk of nocturnal hypoglycemia in children with type 1 diabetes.