BACKGROUND: Stroke is a leading cause of disability resulting in long-term functional ambulation deficits. Conventional therapy can improve ambulation, but may not be able to provide consistent, high dose repetition of movement, resulting in variable recovery with residual gait deviations. OBJECTIVE: The objective of this preliminary prospective investigation is to evaluate the ability of a robotic exoskeleton (RE) to provide high dose gait training, and measure the resulting therapeutic effect on functional ambulation in adults with acute stroke. METHODS: Participants (n = 14) received standard of care (SOC) and RE overground gait training during their scheduled physical therapy (PT) sessions at the same inpatient rehabilitation facility. The outcome measures included distance walked during their PT training sessions (RE and SOC), and functional ambulation measures (10-meter walk test (10MWT), 6-minute walk test (6 MWT), and timed up and go (TUG)). RESULTS: The average total distance walked during RE and the average distance per RE session was significantly higher than SOC sessions. Total walking distance during PT (RE+SOC) showed a strong positive correlation to the total number of steps during RE sessions and number of RE sessions. All functional ambulation measures showed significant improvement at follow-up compared to baseline. The improvement in functional ambulation measures showed a positive correlation with the increase in number of RE gait training sessions. CONCLUSION: The RE can be utilized for inpatient rehabilitation in conjunction with SOC gait training sessions and may result in improved functional ambulation in adults with acute stroke. This preliminary research provides information on the ability of the robotic exoskeleton to provide high dose therapy and its therapeutic effect on functional ambulation in adults with acute stroke during inpatient rehabilitation.