Background- Cardiovascular diseases, especially coronary artery disease (CAD), have reached epidemic proportions worldwide. Potassium plays an important role in relation to electrophysiological functioning of the heart while Magnesium ions are considered essential for the maintenance of functional integrity of myocardium. Both the cations have a significant role in development of arrhythmias in patients of AMI. The present study was undertaken to evaluate the prevalence of arrhythmias in patients of STEMI having electrolyte disturbances at presentation. Aims and objectives 1. To analyze the levels of Potassium and Magnesium in patients of Acute STEMI. 2. To determine hypokalemia and hypomagnesemia as a potential risk factor for arrhythmias in patients of STEMI. Materials and methods- This observational cross-sectional study was conducted in the Medicine Department, Guru Nanak Dev Hospital attached to Govt. Medical College, Amritsar. A total of 100 patients of STEMI were enrolled in this study. Serum magnesium and potassium levels were measured in all the patients and their correlation with clinical outcomes was observed. Results- The mean serum magnesium in patients with arrhythmia was 1.71±0.38 With a statistically significant p value of 0.031 and without arrhy,thmia 1.88±0.32. The mean potassium concentration in patients with arrhythmias 4.02±0.43 with a statistically significant p-value of 0.006. And without arrhythmiasd 3.59±0.63. It was inferred from this study that patients with STEMI with low serum magnesium and potassium levels are more prone to develop complications such as arrhythmias leading to sudden cardiac death as compared to patients of AMI with normal serum magnesium and potassium levels. Conclusion- Serum magnesium and potassium levels do fall significantly in patients of Myocardial infarction. Patients of Acute myocardial infarction with low serum magnesium and potassium levels are found to be more prone to develop arrhythmias as compared to those with normal levels of these electrolytes. Hence, it can be concluded that measurement of serum magnesium and potassium levels are of prognostic significance in AMI.