OBJECTIVES: To evaluate the effect of postmenopausal hormone therapy alone or in combination with bisphosphonate on bone mineral density (BMD) in postmenopausal women. METHODS: One hundred three women diagnosed with low BMD in postmenopausal women were included in this study. All patients were classified into two groups; oarl hormone therpy alone (Group I) or with alendronate (Group II), given for 12 months. Dual energy X-ray absorptiometry was used to measure BMD before and after 12 months of treatment. RESULTS: In all groups, significant increase in bone density measurements were seen at 12 months of treatment. The BMD of lumbar spine more increased significantly in Group II than Group I. CONCLUSIONS: Postmenopausal hormone therapy is effective in osteopenic and osteoporotic women. However, the combined treatment with hormone therapy and bisphophonate is more effective in postmenopausal women with low BMD.