Abstract： Objective To investigate whether the good control of fasting plasma glucose(FPG) has any effects on bone turnover rate in type 2 diabetes mellitus (DM).Methods A series of markers,such as bone specific alkaline phosphatase (BAP),deoxypyridinoline (DPD),were assessed before and after glycemic control for more than 18 days in 43 poorly controlled type 2 DM patients with initial hemoglobin A1c over 8%.Results By either oral hypoglycemic agent or insulin administration,or both, ideal control of FPG resulted in a reduction in the secretion of urinary calcium(Ca),phosphate(Pi) and magnesium(Mg),and an increase in serum Ca and Pi without obvious changes in serum Mg.The marker for bone resorption,urinary DPD and the marker for bone formation,BAP in serum were reduced significantly before and after the management.The results indicated that the decreases both in DPD and in BAP were not only correlated well with each other,but with the improvement in glycemic indices as well.Conclusion Good control of hyperglycemia in poorly controlled type 2 DM may have the high bone turnover rate back to normal and protect type 2 DM patients from bone loss.