To determine the association between serum levels of OCN and metabolic parameters and carotid intima media thickness (CIMT) in a group of post-menopausal females with type 2 diabetes (T2DM). This cross-sectional study comprised 75 postmenopausal women with T2DM (group 1; 25 patients with normal bone mineral density (BMD), group 2; 25 patients with osteopenia and group 3; 25 patients with osteoporosis) and 40 age matched non-diabetic postmenopausal females. All subjects included in this study were subjected to the following: thorough clinical evaluation, laboratory investigations including fasting blood glucose (FBG), glycated hemoglobin (HbA1c) and lipid profile. Bone mineral density (BMD) was measured by DEXA scan. CIMT was assessed with B-mode ultrasonography. Serum OCN was measured using ELISA. Person’s correlation analysis was used to evaluate the relation of OCN to different parameters of the studied population. Multivariate logistic regression model was used to quantitatively analyze the interactions. Although there was no significant difference between patients with T2DM and control subjects in BMD, serum OCN was significantly lower in patients with T2DM compared to control (63.73±27.20 vs 136.16±21.96 pg/mL, P<.001). Also, there was significant reduction in OCN level in diabetic patients with osteoporosis as compared to those with osteopenia and normal BMD. In diabetic patients there was significant negative correlation between serum OCN and CIMT (r= -0.332; P=0.003) (fig.1), FBG (r= -0.732; P< 0.001), serum insulin(r= -0.302; P=0.007), HbA1c (r= -0.672; P< 0.001) (fig.2), HOMAIR (r= -0.672; P< 0.001). Multiple linear regression analysis showed that serum insulin (β= -0.183, P=0.033), FBG (β= -0.604, P< 0.001) and LDL (β= -0.195, P= 0.02) were still negatively correlated with the serum OCN. Serum OCN concentration is reduced in postmenopausal women with T2DM and it is lower in patients with osteoporosis than those with normal BMD. Low serum OCN level is a significant and independent factor associated with worse glycemic profile and higher insulin resistance conferring thus a larger risk of developing atherosclerosis in this group of patients.