This study aimed to investigate the effect of whole-body vibration therapy on lower extremity function in subacute stroke patients. Subacute stroke patients who were able to undergo gait training were randomly divided into a vibration therapy group and a control group. All patients attended 20-min training sessions twice daily, 5 times a week for 2 weeks. Each session included 45 squats. The vibration group trained on a vibration platform and the control group trained on the ground. The degree of maximal isokinetic voluntary contraction torque was evaluated, and manual muscle tests of hip and knee flexion and extension were performed. The Berg Balance Scale, 10-m walk test, Timed Up and Go Test, and Functional Ambulation Category were used. A total of 38 patients, 20 in the vibration group and 18 in the control group, were included in the analysis. After the 2-week therapy, the vibration group showed significant improvements in lower extremity strength, balance, and gait performance. The vibration group showed significantly better performance on the Berg Balance Scale, 10-m walk test, and Functional Ambulation Category than the control group. There were no significant differences in maximal isokinetic voluntary contraction torque or manual muscle tests between the groups. Our results suggest that additional training with whole-body vibration may effectively improve the balance and gait performance of subacute stroke patients. Further studies on large populations are required to determine the therapy's clinical efficacy.