Hypokalemia, characterized by low serum potassium levels, can cause marked alterations in cardiac electrical activity and lead to a range of ECG abnormalities. These changes span from mild findings to severe, life-threatening arrhythmias. A key diagnostic challenge is the resemblance of ECG manifestations of hypokalemia to ischemic heart disease, particularly myocardial infarction with nonobstructive coronary arteries. This overlap can complicate diagnosis, especially in patients presenting with chest pain. This case report describes a patient with severe hypokalemia whose ECG showed changes mimicking ischemic injury, including ST-segment depression, T-wave inversion, and atrial fibrillation. Despite initial concern for myocardial infarction, further evaluation—including normal troponin levels, echocardiographic findings, and selective coronary angiography—ruled out significant ischemia. The patient improved with potassium correction, and subsequent normalization of the ECG supported a diagnosis of hypokalemia-induced changes. This case underscores the importance of rapid potassium correction to prevent adverse cardiac outcomes and highlights the need for careful differential diagnosis when interpreting ECG findings in hypokalemia. (Iranian Heart Journal 2025; 26(4): 85-88)