Objective To assess the efficacies of once-weekly bisphosphonates on bone mineral density (BMD) gains in Korean women aged 50 years or more. Methods We selected 166 patients who received: alendronate 70 mg (n=48), alendronate 70 mg + cholecalciferol 2,800 IU (n=31) or risedronate 35 mg (n=87) for one year. The baseline BMD and the % changes of BMD at one-year were compared among the three medication groups. Results The menopausal status and number of women with osteoporosis was not different among the three groups, but mean age of women was significantly lower in alendronate group. Baseline BMD at L1-4 and femur neck (FN) was similar, but baseline BMD at femur total (FT) was significantly lower in alendronate group. After one-year use, the median % changes of BMD at three sites were similar among the three groups; however, the median values were highest in alendronate + cholecalciferol group (L1-4: 4.48%, 6.74%, and 4.50%; FT: 2.09%, 3.70%, and 2.31%; FN: 3.05%, 3.79%, and 2.03%). Conclusion Among three once-weekly bisphosphonates, BMD gains were highest after one-year use of alendronate+cholecalciferol, although statistically not significant.