Cushing’s syndrome, characterized by hypercortisolism, must be considered in the differential diagnosis of such common clinical problems as hirsutism, hypertension, diabetes mellitus, and obesity and psychiatric disorders. Cushing’s syndrome patients often suffer from major psychiatric syndromes, most often depression. Neuropsychiatric abnormalities are frequently associated with Cushing’s syndrome. A 52-year-old woman was referred to our clinic in 2012, because of night-time sleeplessness, psychomotor excitation, hyperactivity, distractibility, şight of ideas, and grandiose delusions. She had been diagnosed as diabetes mellitus and hypertansion on the course of her first manic episode when she was 48 years old in 2009. She has central obesity, facial plethora, hirsutism, abdominal striae, moon face. Investigations showed sodium 137 mmol/L, potassium 2,5 mmol/L. Plasma glucose was 223 mg/dL and hemoglobin A1C 7,9%. Substantially increased values for 24-hour urinary free cortisol (1957 µg/d; reference range, <50), serum cortisol (40 µg/dL; reference range, 8 to 25), and plasma ACTH (178 pg/mL; reference range, 6 to 59) were found, and a diagnosis of ectopic Cushing syndrome was made. This case was diagnosed as Cushing’s syndrome on the course of her second manic episode. Cushing’s syndrome is frequently accompanied by mood disorders, which may be the predominant symptom, and can take many forms, ranging from mania to severe depression. A study reported that, Cushing’s syndrome might refer to clinic only by manic episodes, without any typical symptom. It should be considered that manic or depressive episodes of acute onset might be caused by Cushing’s syndrome.