Abstract: Objective: To explore the operation method and observe the efficacy of treating renal cystic diseases by retroperitoneal laparoscopy.Methods: Thirty-six patients with renal cystic diseases were treated with retroperitoneal laparoscopic cyst decompression,including:32 cases with simple renal cyst,3 cases with polycystic kidney and 1 case with parapelvic cyst.Results: The operations were successfully in all 36 patients without changing to opening operation.The operation time of simple renal cyst was 30-90 min,polycystic kidney was 90-120 min and parapelvic cyst was 110 min.The blood loss of simple renal cyst was <30 ml,the two others were <50 ml.The hospital stay was 3-6 days,6-8 days and 7 days respectively.Patients were followed up for 3-12 months,all cases were no recurrence.In 3 cases with polycystic kidney,lumbar pain was relieved.The renal function of 1 patient with renal insufficiency was got better.The pressure of 1 patient with high blood pressure preoperative was decreased to normal level.Thirty-six cases were no severe complications.Conclusions: Retroperitoneal laparoscopic cyst decompression is an optimum method for treating renal cystic diseases with the advantages of good curative effect,minimal trauma,rapid recovery and short hospitalization,it will be worthy of clinical recommendation.