Objective: The purpose of this study were to investigate the standing balance, dynamic activity in hemiplegic patients according to the types of ankle-foot orthosis(AFO) and to determine the most effective type of AFO for gait training. Method: A prospective study was performed for 16 patients with hemiplegia who was able to walk independently. Static balance and dynamic activity were compared in two condition : 1) barefoot and SPAFO, 2) barefoot and HPAFO. Static balance and dynamic activity characteristics were evaluated by Active Balance while they were standing with in two condition AFO and barefoot. Results: There were significant difference in standing balance between barefoot and wearing SPAFO and HPAFO(p<0.05). There were significant difference in dynamic activity balance between barefoot and wearing SPAFO and HPAFO(p<0.05). There were significant difference in gait speed between barefoot and wearing SPAFO and HPAFO(p<0.05). Conclusion: This study showed that wearing SPAFO and HPAFO gave fair amount of improvement to balance and gait ability of hemiplegic patients.