Objective To investigate the effect of metabolic syndrome(MS) on old female patients with initial acute ST-elevated myocardial infarction(STEMI)and to analyze the influence of MS on prognosis of these patients so as to take more effective measures to prevent severe complications.Methods Ninety STEMI patients were registered to this study,who had been hospitalized in Xuanwu Hospital from March,2005 to June,2007.The zero time was defined as the date of hospitalization while the end-point was defined as the patient’s death.And then a two years follow-up was proceeded to investigate the outcome,including the recurrence of acute myocardial infarction or angina pectoris,the situation of cardiac function,the incurrence of re-hospitalization and cardiac death.Results Recurrence rates of angina pectoris and re-infarction in MS group were higher than those in the control group(P<0.05).There was no difference in incurrence of re-hospitalization and mortality between the two groups.Conclusion MS leads to higher recurrence rates of angina and re-infarction in old female acute myocardial infarction patients.MS should be treated more seriously and a comprehensive treatment should be proceeded to prevent the recurrence of cardiac events.