Background: Acute myocardial infarction (AMI) is a condition where there is a formation of thrombus which reduces the blood flow in the coronary arteries resulting in coronary vasospasm, further leading to cardiac muscles dysfunction or even death. Quick and accurate diagnosis of AMI plays a major role in the management and prognosis of this disease. Circulating miRNA has been a promising cardiac biomarker for AMI as well as cardiovascular disease in recent years. In the circulation miR 1 overexpressed when there is any damage in the cardiac cell. A very few articles documented the use of miR-1 as a diagnostic marker in AMI. The aim of the study was to find the diagnostic and prognostic role of miR-1 in AMI. Methodology: In this study, 62 AMI patients in the age group of 30–75 years and 30 healthy controls were included. Blood samples were collected at a different time of admission, 6 hours, 12 hours, 24 hours and 72 hours for the subject. Serum was separated immediately for the analysis of CK (NAC) and CK MB, Hs troponin T and micro-RNA-1 was quantification by RT-PCR. To study the kinetics of miR-1 repeated measure of analysis of variance (ANOVA) was analyzed. To find the diagnostic utility AUC, likelihood and odd's ration was performed. Results: The miR-1 expression is expressed in a change in fold 27.36, 57.17, 43.55, 32.50 and 24.09 fold increase at the different time. The study revealed that the sensitivity 69%, specificity 66%, LR was 1.59 and OR 4.04 in the differential diagnosis of AMI. Conclusion: In a total expression of miR-1 showed statistical significance in different time internal which will help us to use in the differential diagnosis of AMI.