Objectives: The clinical characteristics and prognosis of youngwomen (= 50 years) with acute coronary syndrome (ACS) are still unclear. Methods: A total of 5196 patients with ACSwere enrolled fromthe cardiac center of Chinese PLA General Hospital and AnzhenHospital. The clinical characteristics of these patientswere analyzed. Then the PubMed, EMBASE, and Cochrane Central Register of Controlled Trials electronic databaseswere searched fromJanuary 2001 to July 2016. Clinical trials that performed comparisons prognosis of young women versusmen with ACS were considered for inclusion. Results: The young men had higher BMI, had increased incidence of hyperlipidemia, and were more likely to smoke, drink alcohol, and have had a previous MI. There was a higher proportion of unstable angina (UA) in women than in men (P < 0.05). The proportion of thrombolysis myocardial infarction (TIMI) 0 in women was lower than in men (P = 0.001), and the proportion of TIMI 3 was higher in women than in men (P = 0.000). The mortality of in-hospital, short-term, and long-term rate was significantly higher in women than that in men (6.2% vs 2.9%, OR = 1.84, P b 0.001; 16.4% vs 11.5%, OR = 1.66, P = 0.007; 8.9% vs 3.0%, OR = 1.41, P = 0.008), but there were no significant differences in the rates of major adverse cardiac events (MACE). Conclusions: In young women patients with ACS, the mortality rate during in-hospital, short-term, and longerterm follow-up inwomen was higher than that inmen. Thus, young womenwith ACS needmore attention during clinical diagnosis and treatment. (C) 2016 Elsevier Ireland Ltd. All rights reserved.