Objectives: To compare outcomes by age and sex in race/ethnic minorities presenting with ST-elevation myocardial infarction (STEMI), as studies are limited. Methods: We studied sociodemographics, management, and outcomes in 1208 STEMI patients evaluated for primary percutaneous coronary intervention between 2008 and 2014 at Montefiore Health System (Bronx, NY). A majority of patients self-identified as nonwhite, and nearly two-thirds were young (<45 years) or middle-aged (45-64 years). Results: Risk factors varied significantly across age groups; with more women and non-Hispanic whites, hypertension, diabetes, dyslipidemia, prior cardiovascular disease, non-sinus rhythm, and collagen vascular disease in the older age group (≥65 years); and higher body mass index, smoking, cocaine use, human immunodeficiency virus (HIV) infection and family history of heart disease in the young. Younger women had lower summary socioeconomic scores than younger men. Middle-aged women had more obesity and dysmetabolism, while men had more heavy alcohol use. There was greater disease severity with increasing age; with higher cardiac biomarkers, 3-vessel disease, cardiogenic shock, and coronary artery bypass grafting. Older patients had higher rates of death and death or readmission over 4.3 (interquartile range 2.4, 6.0) years of follow-up. Middle-aged women had higher rates of death or any readmission than men, but these differences were not significant after adjustment.