Patients with diabetes mellitus (DM) have chronically increased blood glucose and multiple physiologic alterations that place them at elevated risk for vascular disease. Traditionally, this vascular risk has mainly referred to chronic atherosclerosis and embolic arterial disease. Retrospective studies have suggested an increased risk of a pulmonary embolism (PE) and deep vein thrombosis (DVT), collectively termed venous thromboembolism (VTE), in patients with DM, but this association has been difficult to demonstrate with comorbidities such as obesity in meta-analysis. Clinical studies have demonstrated worse outcomes for patients with DM who suffer from VTE. In vitro studies show multiple physiologic abnormalities with chronic inflammation, endothelial dysfunction, dysfunction in the coagulation cascade, as well as other changes that drive a vicious cycle of hypercoagulability. Aggressive medical management of DM can improve vascular outcomes, and some anti-hyperglycemic therapies may modify VTE risk as well. Anticoagulation strategies are similar for patients with DM, but with some added considerations, such as high rates of comorbid renal dysfunction. More research is needed to definitively categorize DM as a risk factor for VTE and elucidate specific therapeutic strategies.