Although hirsutism is classically part of the clinical presentation of polycystic ovarian syndrome (PCOS), congenital adrenal hyperplasia and Cushing's syndrome (CS), CS associated with underlying late-onset congenital adrenal hyperplasia (LCAH) in an adult has not been previously reported. We herein present the case of a 25-year-old woman who was followed for PCOS for seven years. After undergoing detailed tests described within the text, she received the diagnosis of LCAH and was found to have point mutations. Interestingly, she later had diagnosis of endogenous CS that regressed folowing excision of an adrenal adenoma found on MRI. The present patient thus exhibited the coexistence of two paradoxical endocrine pathologies.