Rising rates of both type 1 and type 2 diabetes mellitus in children have led to increased concern regarding cardiovascular disease (CVD) risk during childhood. Diabetic children face prolonged exposure to hyperglycemia, and have increased risk of both microvascular and macrovascular disease. These circumstances may result in a generation of young adults presenting with cardiovascular outcomes, a tremendous personal and public health toll. In this article, we review CVD risk in type 1 and type 2 diabetes, discuss aspects of pathophysiology, and review current methods of CVD risk assessment. We also identify crucial areas in need of future research in order to devise effective prevention and treatment of CVD risk in children.