Abstract: From April 1987 to April 1996 6 patients with bilateral renal cell carcinoma were treated in our hospital. This series included 2 patients with synchronous and 4 with asynchronous diseases. Patients in the latter group had operated on with contralteral radical nephrectomy sometimes before. All patients had undergone nephron sparing surgery for renal cell carcinoma and were followed up for 2 months to 9 years （mean 41 months） postoperatively. All patients were alive, without any tumor recurrence or metastasis during the follow up period. The incidence, diagnosis, treatment and prognosis of bilateral renal cell carcinoma were discussed.