[Purpose] This study aims to investigate the effects of robotic exoskeleton-assisted gait training on a pediatric patient with peripheral polyneuropathy. [Participant and Methods] A 10-year-old boy with lower extremity weakness attributed to peripheral polyneuropathy underwent a two-week program comprising 10 rehabilitation sessions of powered robotic exoskeleton-assisted gait training (REGT). He was evaluated before and after treatment using the 10-meter walk test, 6-minute walk test, Berg Balance Scale, the Timed Up and Go Test, the Functional Reach Test, the Modified Functional Reach Test, hip and knee flexion/extension angles, and cardiopulmonary exercise testing. [Results] The patient demonstrated improved gait speed, balance, joint mobility, cadence, the maximum oxygen consumption and metabolic equivalents after the REGT. [Conclusion] Robotic exoskeleton devices could provide additional benefits to pediatric patients with peripheral polyneuropathy, pending larger studies to confirm the significance of treatment.