Exposure to high levels of endogenous or exogenous glucocorticoids suppresses the inflammatory response genes. Excessive endogenous hypercortisolism may mask the active inflammatory diseases. Rebound immune modulation may occur after Cushing's syndrome (CS) remission, leading to the new onset of autoimmune diseases. Here, we report a 27-year-old female patient who was recently diagnosed with sarcoidosis after remission of CS. Normal thorax imaging showed that the patient was free of disease during the course of CS and without any symptoms of sarcoidosis. After complete remission of CS, she was diagnosed with sarcoidosis based on clinical and radiological evidence. Excessive hypercortisolism may suppress the active inflammatory stage of sarcoidosis. However, the disease became apparent after the reduction of cortisol levels following the treatment of CS.