Diabetes mellitus is one of the costliest chronic pathology worldwide with a continuous rising incidence. Diabetes mellitus is linked to frequent cardiovascular events. It is associated with vascular events, especially when the glycated hemoglobin has elevated values. Diabetic patients seem to develop abnormalities of the haemostatic process, such as alterations of the thrombocytic function, modifications of the coagulation and of the fibrinolysis that lead to a thrombophillic status. The acquired thrombophilia present in diabetic patients may be due to the non-enzymatic glycosilation of clotting inhibitors such as antithrombine. Antithrombin III has both an anticoagulant and an antiinflammatory effect. The anticoagulant effect appears after acting upon endothelial heparan sulfate or on the molecule of heparine, thus leading to an inhibition of thrombin. A decrease in antithrombin III levels may lead to a diminished neutralisation of thrombin and a lower activity of proteins C and S, thus inducing procoagulant consequences and increasing the susceptibility for thrombotic events. Our research tried to establish whether the levels of antithrombin III in type 2 diabetic patiens are modified, thus creating a predisposition for thrombotic events. Therefore we conducted an observational study on a sample composed of 60 patients having a diagnostic of type 2 diabetes associated with coronary artery disease, controlled with diet or with oral antidiabetics and we evaluated the levels of antithrombin III in function of the metabolic, inflammatory and coronarographic parameters. Our research showed that even though all patients were characterized by the diabetic dyslipidemia, there was no statistic relationship between antithrombin III and the lipidic fractions. As a result we cannot say that the adverse cardiac events seen in type 2 diabetic patients are influenced by the levels of antithrombin III, as a marker of an increased clotting activity.