A rare case of symmetric renal extramedullary hematopoiesis is hypothesized in a patient with long-standing Vaquez' disease and myelofibrosis. At CT, soft tissue densities were found in the renal hilar area encasing the pelvicalyceal system. Although there is nothing specific about the CT findings, the diagnosis can be suggested in the proper clinical setting. The association with generalized osteosclerosis is another diagnostic clue.