The purposes of this study were to determine the effects of rehabilitation programs on functional performance of the lower extremities and whether additional therapeutic exercise with routine rehabilitative therapy improves functional performance more than just routine rehabilitative therapy by it self for inpatients who have suffered a stroke with below moderate severity within 3 to 6 months after the onset of the stroke. Fifty-eight subjects were divided into two groups. Group I was given routine rehabilitative therapy and group II was given additional therapeutic exercise along with the routine rehabilitative therapy. Each group received 6 weeks of rehabilitation. The timed get-up and go test (TUG), the Fugl-Meyer score (FMS), functional independence measure (FIM), functional reach (FR), gait velocity (GV), and the strength of knee extensor and flexor were selected to measure effect of rehabilitation programs. The main results were measured and analysed at baseline, 3 weeks, and 6 weeks after the start of the rehabilitation programs. The results revealed that all of functional performance of the lower extremities in 3 weeks after the start of the rehabilitation programs were significantly improved compared with before the rehabilitation programs in both groups. In 6 weeks, TUG, FIM, FR, GV, and the strength of knee extensor in group I, TUG, FMS, FIM, FR, GV, and the strength of knee extensor and flexor in group II were significantly improved compared with the results after 3 weeks. At 3 weeks after rehabilitation programs, group II made significantly greater gains in TUG, FR, GV, and the strength of the knee flexor compared to the group I. At 6 weeks, group II made significantly greater gains in TUG, FR, GV, and the strength of the knee extensor and flexor compared to the group I. In conclusion, rehabilitation programs for stroke patients within 3 to 6 months after stroke onset significantly contributed to improve functional performance of the lower extremities. It is desirable for improvement of functional performance of the lower extremities to perform additional exercise with routine rehabilitative therapy.