Enhancing vagal tone by delivering electrical stimulation to the vagal nerves (VNS) is emerging as a promising novel therapy in heart failure. In addition, VNS is already an FDA-approved therapy for refractory epilepsy and depression. Besides its well-known negative chronotropic, inotropic, and dromotropic effects, VNS has profound effects on cardiac electrophysiology and arrhythmogenesis. This review summarizes current knowledge about the complex relationship between VNS and cardiac arrhythmias. Specifically, the focus is on VNS capability to become a therapeutic strategy along with important electrophysiological alterations that may constitute a potential arrhythmogenic substrate and become a clinical concern.