Renal osteodystrophy in hemodialyzed patients with DM-HD shows different features from that in non-DM,HD. Two studies were done. One was a comparison of BMD in 30 non-DM,HD patients and 30 DM-HD patients. The second was a comparison of possible factors affecting calcium metabolism in the higher and lower BMD groups (n = 20/21) in the DM-HD patients. BMD was measured by dual-energy X-ray absorptiometry (DEXA; Hologic QDR 1,000/W) in the third lumbar vertebra (L3), head, pelvis, and whole body. The BMDs of the DM-HD group were lower in these areas and whole body than that in the non-DM,HD group. A significant difference was found in the head BMD (p less than 0.05). In the second study, factors which may contribute to the differences in BMD were compared in the DM-HD patients divided into higher and lower BMD of the head. The group with higher head BMD had a value 110% of the mean value or more. Clinical and biochemical test results (age, the time since the first dialysis, body weight, the degree of obesity, height, serum calcium, serum phosphate, serum aluminum, serum c-PTH level and the dose of 1 alpha-OH-D3) were compared. The degree of obesity of the patients with higher BMD was significantly larger than that with lower BMD (p less than 0.005).