Atherosclerosis is the main cause of cardiovascular disease (CVD) which is the major cause of morbidity and mortality for diabetic patients. Endothelial dysfunction, which occurs early in atherogenesis, is associated with endothelial expression of the cell-surface adhesion molecules such as ICAM-1 (intercellular adhesion molecule-1). A soluble form of ICAM-1 can be measured in serum. Our study is a prospective cross-sectional study which included 65 participants aged 45-72 years and divided into three groups: type 2 diabetic atherosclerotic patients (n=24), type 2 diabetic non-atherosclerotic patients (n=20) and control group (n=21). Levels of sICAM-1, fasting blood glucose (FBG), total cholesterol (TC), triglycerides(TG), LDL-C and HDL-C were measured. sICAM-1 levels were significantly higher in diabetic atherosclerotic patients compared to diabetic patients (P<0.001) and control group (P<0.001) [470.94±15.24 ng/ml, 336.18±28.32 ng/ml, 273.46±7.2 respectively]. sICAM-1 levels were also significantly higher in diabetic patients compared to control group. Levels of sICAM-1 correlated positively and significantly with FBG and BMI values in diabetic atherosclerotic patients and diabetic patients whereas the correlation was not significant between sICAM-1 levels and lipid parameters levels. Our results showed that type 2 diabetes and atherosclerosis induce significant increase in sICAM-1 levels as a marker of endothelial activation. The coexistence of diabetes and atherosclerosis induces higher levels of sICAM-1.