Background: Diabetic osteoporosis is caused by reduced bone mineral content due to the abnormal levels of sugar, protein, fat, and macroelements, such as calcium and phosphorus. Beside metabolic bone diseases, these changes at times lead to pathological fractures. Still, the effect of type 2diabetes (T2DM) on bone mineral density remains controversial. There are potential mechanisms behind the increased fracture risk that occurs in patients with diabetes, even those with increased bone mineral density. One potential link between diabetes and bone is the osteoblast-produced factor, osteocalcin. Objective: The aim of this study was to determine the level of osteocalcin in type 2 diabetic patients as a marker for early detection of osteoporosis. This may help early prediction and treatment of osteoporosis before bone mass density (BMD) affected. Subjects and Methods: Sixty diabetic patients (30 males and 30 females) aged33 –61years were recruited and classified by DEXA into three equal groups: patients with type 2 diabetes mellitus with osteoporosis, patients with osteopenia, and patients with normal bone, as well as twenty apparently healthy controls. The inclusion and exclusion criteria were applied for both patients and controls. All subjects included in this study were subjected to the following : Full history taking and clinical examination , laboratory investigations including complete blood picture (CBC) , fasting and post prandial serum glucose levels, serum creatinine, lipid profile (LDL, HDL, total cholesterol and triglycerides) and complete urine analysis. Serological test for osteocalcin by ELISA technique was used.  Results:  The results of the present study showed that serum osteocalcin level significantly decreased in diabetic patients with osteoporosis, osteopenia and normal bone as compared to healthy control subjects. Also, there was significant decrease in serum osteocalcin level in type 2 diabetic patients with osteoporosis as compared to those with osteopenia and normal bone density groups. Significant negative correlation was found between osteocalcin and HbA1c, LDL, duration of diabetes and TG in all diabetic patients groups, and positive correlation between osteocalcin, HDL, and BMD in all diabetic groups. Conclusion: Osteocalcin may have a role on prediction of osteoporosis in diabetic patients even before bone mineral density affected.