Purpose The Purpose of this study was to investigate the effect of virtual reality training on the balance of chronic stroke patients on an unstable surface. Methods The subjects were 10 chronic stroke patients who have been diagnosed with stroke for more than six months. Five subjects were assigned to the experimental group and five to the control group. Virtual reality training was performed using GymPlate, and a balance pad was placed on the foot plate of the GymPlate. Then the subjects were evaluated by LOS, BBS, and TUG. Results The results of this study showed that in the experimental group, there was a significant difference in LOS and TUG (P<0.05) before and after the intervention, but there was no significant difference in BBS (P>0.05). In the control group, there was no significant difference in LOS, BBS, and TUG before and after intervention (P>0.05). Furthermore, there was a significant difference in LOS and TUG (P<0.05) after the intervention compared to before the intervention in the experimental and control groups, but there was no significant difference in BBS (P>0.05). Conclusion Virtual reality training on an unstable surface by symmetrical weight support and weight shift is effective in improving balance ability in patients with chronic stroke.