Totally subcutaneous implantable cardioverter-defibrillator（S-ICD）system has been available in Japan since February 2016. S-ICD avoids important periprocedual and long-term complications associated with transvenous leads of the conventional ICD such as lead dislodgement or infective endocarditis. To assess who is suitable for S-ICD, patients are required one lead to satisfy the S-ICD screening template. However, evaluation of the screening ECG only performed once while at rest may be insufficient for patients with diurnal variation and day-to-day variations of ECG such as Brugada syndrome（BrS）. Here we report a case of BrS who passed the S-ICD template one day, but failed another day. A 58 year-old man with BrS came to our hospital for lead injury of implantable cardioverter-defibrillator（ICD）. S-ICD implantation was considered for him. He passed S-ICD template one day but failed another day. Therefore, he was assessed by treadmill exercise test and Holter ECG to simulate the 3 S-ICD sensing vectors. During these tests, the eligibility of S-ICD changed dramatically, and we gave up implanting S-ICD for him. The ECG morphology changes dramatically by situation in patients with BrS. Holter ECG and exercise stress test should be considered before S-ICD implantation in patients with BrS.