OBJECTIVE To evaluate and compare the efficacy and safety of the combination of raloxifene and alendronate with those of monotherapies in elderly women with osteoporosis. METHODS Sixty-two postmenopausal women (mean age 63.5 ± 0.5 years) attending gynecologic osteoporosis clinics with established osteoporosis were randomly allocated to one of four treatment groups and monitored for 3 years. All patients enrolled in this study, including those in the control group (n = 14), received 1.0 g elemental calcium and 400 units of vitamin D per day. The raloxifene group (n = 16) received raloxifene 60 mg (Evista®) per day; alendronate group (n = 17) received low-dose (5 mg) alendronate with calcitriol 0.5 µg (Maxmarvil®) per day; and the combination therapy group (n = 15) received both raloxifene 60 mg and low-dose (5 mg) alendronate with calcitriol 0.5 µg. Bone mineral density (BMD) was measured in the lumbar spine and hip before and after 3 years of treatment. RESULTS In patients who received the combined therapy, BMD increased in the lumbar spine and the hip by 7.2% (P<0.001) and 4.8% (P<0.001) at 3 years. For patients in the alendronate group, the increases were 6.7% (P<0.001) and 3.1% (P<0.01) respectively, for the raloxifene group, the increases were 4.36% (P<0.001) and 1.9% (P<0.05) in the vertebrae and femora, respectively; however, the BMD of patients in the control group decreased by 1.81% (P<0.05) and 1.6% (P<0.05), respectively, after 3 years. Patients who received the combination therapy had significantly higher BMD in both the vertebrae femora (P<0.01) in comparison to that in those treated with raloxifene or alendronate individually. CONCLUSIONS This 3-year randomized study showed the improved effects of alendronate and raloxifene combination on spine and hip BMD in elderly postmenopausal women with established osteoporosis.