Recently, diabetes has been found to be associated with osteoporosis. Specially in IDDM. In both type I and type II diabetes, glucose levels are elevated. Thus, a linkage between high glucose and osteoporosis can not be ruled out. In this study, an attempt has been made to observe the effect of high glucose on bone formation; osteoblast like UMR 106 cells were treated with high glucose (22 mM, 33 mM) for 1, 3 or 7 days. The high concentration of glucose inhibited markers. of bone formation activity such as alkaline phosphatase and collagen synthesis. In addition, reduction in the level of total cellular protein in response to high glucose was also observed. This study showed high glucose concentration could alter the bone metabolism leading to a defective bone formation and thus paving the linkage of such situation to diabetic complications.