Spontaneous regression of metastases or primary lesions of malignancy is a most intriguing phenomenon. However there were no reports of spontaneous regression of primary renal cell carcinoma. We reviewed a case of renal mass which was considered to be a spontaneously regressed renal cell carinoma. This diagnosis was supported by the size of the renal mass, its total necrosis, and the discovery of a few remaining tumor cells. We cautiously report this case as a spontaneously regressed primary renal cell carcinoma in a 54 year old woman.