The aim of this pilot study was to investigate the feasibility of high-speed gait training with an exoskeleton robot hybrid assistive limb (HAL) in patients with chronic stroke, and to examine the efficacy of eight sessions (8 weeks) of gait training with a HAL compared with conventional physical therapy. Eighteen patients with chronic stroke were included in this study (nine each in the HAL and control groups). The HAL group underwent high-speed gait training with the HAL once a week for 8 weeks (20 min/session). The control group underwent conventional physical therapy for gait disturbance. Outcome measures were walking speed, number of steps, and cadence during a 10 m walking test, a timed up and go test, a functional reach test, and the Berg Balance Scale. Assessments were performed in the absence of the HAL before training and after the fourth and eighth training sessions. All patients in the HAL group completed the high-speed gait training without adverse events. The HAL group improved significantly in walking speed (55.9% increase, P<0.001), number of steps (17.6% decrease, P<0.01), and cadence (32.8% increase, P<0.001) during the 10 m walking test. The patients also exhibited significant improvements in the timed up and go test, the functional reach test, and the Berg Balance Scale after HAL training (P<0.01 in all). No statistical time-dependent changes were observed in any parameter in the control group. For chronic stroke patients, high-speed gait training with a HAL appears to be feasible and effective in improving gait and balance dysfunction despite the limitations of this nonrandomized pilot study.