Abstract    BACKGROUND: This study aimed to investigate 28-day case fatality rate due to acute myocardial infarction (MI) in Isfahan using a standardized surveillance system.    METHODS: A prospective longitudinal study was performed on hospitalized myocardial infarction patients in Isfahan, Iran from 2000 to 2004. All hospitalizations due to myocardial infarction (MI) events were recorded via a system adopted from “World Health Organization Monitoring Trends and Determinants in Cardiovascular Disease” (MONICA) project, with ignoring MONICA age limitation. Patients were followed and their families enquired about their patients survival status at 28th day with phone calls and if not available at home visits.    RESULTS: Age-adjusted hospital admission rate showed an increase during the study period, rising from 131.67 to 209.27 per 100000, but slowed toward the end of the study. Patients’ mean age was 62.35±12.64, with one third of events documented among female patients. Young patients (< 45 years old) comprised 8.6% of hospitalizations which remained nearly constant through the study. The corresponding figure was about 28% for patients aged less than 55 years. The 28-day case fatality rate was 23.1% for women and 13.2% for men. For individuals aged 35-64 years, the fatality rate was 13.0% for women and 7.7% for men.     CONCLUSION: This study showed an increase in myocardial infarction hospital admission rate in Isfahan but the rate of increase is decreasing. A multi-centric community-based myocardial infarction incidence study is needed to elucidate myocardial infarction epidemiology in Iran.      Keywords: Myocardial Infarction (MI), Epidemiology, Prevention and control, Cardiovascular diseases, Iran, Fatality rate.