Severe hyperthyroidism can cause the injuries of multiple organs including heart and liver and ultimately be fatal. A 26-year-old young woman admitted to Peking Union Medical College Hospital for severe hyperthyroidism due to irregular use of anti-thyroid drugs. She had heart failure,atrial fibrillation,and severe liver damage at admission. Anti-thyroid drugs were then actively used to treat the primary disease,along with interventions to correct heart failure and control atrial fibrillation. Severe total bilirubin elevation was found during the treatment, which was resolved after the use of glucocorticoid and liver-protective therapy. The patient was regularly followed up after discharge,and the clinical manifestations were good.