There are some difficulties in differential diagnosis of prenatally detected adrenal cystic masses. Diagnostic possibilities do not only consist of benign lesions such as adrenal hemorrhage, simple cyst, renal duplication and pancreatic cyst but neuroblastoma also. Here in we reported a case of cystic neuroblastoma presented as a prenatally detected adrenal mass. His postnatal ultrasonography and MR imaging studies verified the right adrenal cystic mass, exact diagnosis could be established with histopathological investigation after removal of the cyst. Patients with prenatally detected adrenal cyst should carefully be followed after birth.