Subcutaneous implantable cardioverter-defibrillators (S-ICD) provide an effective treatment option for ventricular arrhythmias. When compared to transvenous implantable cardioverter-defibrillators (TV-ICDs), S-ICDs have a lower infection rate but a higher rate of inappropriate shocks. In patients with end-stage renal disease (ESRD), significant electrolyte disturbances are commonly seen, such as hyperkalemia, which can cause an increase in T wave amplitude. We present a patient with ESRD on hemodialysis who experienced inappropriate shocks from an S-ICD during sinus rhythm due to hyperkalemia-induced T wave oversensing and highlight related cases in the current literature.