Macroangiopathy is multifactorial. It is more severe and frequent in association with nephropathy in diabetes mellitus (DM), being the first cause of mortality in both types of DM. Nevertheless, it is poorly understood in young patients. We report on 2 young diabetic patients with early-onset coronary disease. Case 1, 40 yo, Caucasian, female, type 2 DM for 21 y: treated with sulphonylureas until 25 y, she was switched to insulin upon becoming pregnant. Preeclampsia ensued, but no premature delivery occurred. Macroproteinuria remained (0.99 g/24 h), and she progressed to renal failure (clearance 52.7 mg/min) (conservative treatment). At age 36, she had an acute myocardial infarction. Severe tri-arterial disease was diagnosed, and coronary bypass grafting (CABG) performed. Case 2, 34 yo, black, female, type 1 DM for 24 y: diagnosed by diabetic ketoacidosis. Due to poor metabolic control (HbA1c chronically above 4 points beyond upper limit for normal) she progressed to microalbuminuria (0.26 g/24 h) at age 22, after pregnancy. Macroproteinuria (1.7 g/24 h) ensued after a second pregnancy. At 31 y, she presented with stable angina. After coronary angiography, CABG was indicated. These two cases of macroangiopathy in patients diagnosed with DM at an early age show acceleration in the development of coronary disease, suggesting aggressive multifactorial approach of related risk factors from the beginning, regardless of its etiology.