Evolocumab is a recently FDA-approved proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9i) that reduces the risk of myocardial infarction, stroke, and coronary revascularization in individuals with established atherosclerotic cardiovascular disease. We report an extremely rare possible side effect, atrial fibrillation (AF), encountered with evolocumab to increase the awareness among physicians of such a possibility.