The purpose of this study was to investigate the effects of whole-body vibration on the improvement of functional performance in subacute stroke patients. Methods: Twenty subacute stroke patients were equally randomized to either a vibration or a control group and received 4-week conventional rehabilitation therapy and standing exercise. During the standing exercise, the vibration group received 10-minute whole-body vibration and the control group performed standing exercise without vibration. Outcome variable included the Korean version of Berg Balance Scale (BBS), the manual muscle test (MMT) of the paretic knee extensor, Modified Ashworth Scale (MAS) of the paretic ankle plantar flexor spasticity, Functional Ambulation Category (FAC), and the Korean version of Modified Barthel Index (MBI) before and after 4-week intervention. Results: After the 4-week intervention, the difference in BBS between groups was significant, which was significantly larger in the vibration group than in the control group. Significant differences in FAC and MBI were also observed between groups. The change of the FAC, total MBI, and mobility MBI were significantly higher in the vibration group than in the control group. MMT and MAS did not show significant difference after intervention between groups. Differences in BBS were strongly positively correlated with FAC and mobility MBI, and were moderately correlated with both of total MBI and self-care MBI. Conclusion: Additional whole-body vibration intervention may efficiently improve balance control and ambulation in subacute stroke patients.