Aims The role of apolipoprotein A in early onset ST-segment elevation myocardial infarction is not clear. This study sought to assess the apolipoprotein A in cohort of patients diagnosed with early onset acute ST-segment elevation myocardial infarction and to corelate it with major traditional cardiovascular risk factors. Methods A total of 50 such patients and 40 age and sex-matched healthy controls, both aged less than 50 years with their baseline demographic, clinical characteristics and cardiovascular risk factors were studied. Apolipoprotein A was estimated for all enrollees. Results The mean age of cases was 43.37 ± 5.85 years. The levels of apolipoprotein A among cases were not significantly lower compared to controls (P = 0.52). They were lower among the male, current smokers and the dyslipidemia (P’s < 0.05). Considering the apolipoprotein A as the dependent factor, the early onset ST-segment elevation myocardial infarction was associated significantly with the male and the dyslipidemia in linear regression (P < 0.001 and 0.030), respectively. Conclusion Lower levels of apolipoprotein A are significantly related to conventional risk factors in early onset ST-segment elevation myocardial infarction. This apolipoprotein A that particularly develops in young patients with clustering of traditional cardiovascular risk factors should be targeted. Further studies are warranted to determine the diagnostic and prognostic indicators of this apolipoprotein in ST-segment elevation myocardial infarction.