Prednisolone (PSL) therapy is the gold standard treatment in patients with cardiac sarcoidosis (CS). However, clinicians often have difficulty in deciding whether to discontinue PSL therapy in long-term management. Sixty-one consecutive patients with CS were divided into 2 groups based on the discontinuation of PSL during the median follow-up period of 9.9 years. PSL was discontinued in 12 patients because of improvement of clinical findings. There were no significant differences between the 2 groups in age, gender, left ventricular ejection fraction (LVEF), findings of imaging techniques, incidence of fatal arrhythmias and heart failure, and dose of PSL. After discontinuation of PSL, 5 patients had cardiac death, and discontinuation of PSL was significantly associated with higher cardiac mortality compared with continuation (p = 0.035). Although patients with discontinuation had improvement of LVEF after PSL treatment, LVEF decreased after discontinuation of PSL. Furthermore, discontinuation of PSL was associated with greater percent decrease in LVEF compared with continuation (p = 0.037) during the follow-up period. In conclusion, in the long-term management of patients with CS, discontinuation of PSL was associated with poor clinical outcomes and decreased LVEF, suggesting the importance of PSL maintenance therapy.