Criteria are discussed, that according to the literature data allow one to consider adrenocortical tumors without cell polymorphism and mitoses as malignant ones. Such criteria include a rapid tumor growth and its large dimensions, necrotic foci, invasion of blastomatous elements into the capsule and their presence in the vascular lumen. A 47-year old female patient is reported with a rapidly growing large neoplasm of the right adrenal. This adrenocortical tumor in spite of the fact that it lacks polymorphism and mitoses of cells is considered as a malignant one (prevalence of cells with an insignificant amount of lipids, extensive necrotic foci, capsular invasion and evidence of tumor cells in the vascular lumen).