Introduction & Objective:: PCNL is the treatment of choice for renal calculi larger than 20-3o millimeter, staghorn stones and stones that are multiple or resistant to ESWL. The aim of this study was the evaluating of the impact of spinal anesthesia on intraoperative and postoperative outcome in patients undergoing PCNL. Material & Methods: The intraoperative and postoperative anesthetic and surgical variables were evaluated for hundred and twenty consecutive patients underwent PCNL. Anesthetic and surgical variables during and after operation in patient undergoing PCNL under spinal anesthesia were recorded and collected data were analyzed by SPSS software using chi square test. Results: Mean time of operation from the beginning of anesthesia to the end of operation was 98±45 minutes. Mean stone size was 3.1±1.8 cm. Mean time for return of sensory and motor activity were135±22.7 and 112±35.7 minutes respectively. Major intraoperative or postoperative complications such as visceral or vascular injury and unusual bleeding did not occur in any of patients. Five patients needed transfusion of 1 unit pack cell and four patients complain from mild to moderate headache and dizziness and also mild low back pain for 2-4 days after operation that improved with analgesics and bed rest. Conclusion: Spinal anesthesia is safe and effective and also comfortable for performing PCNL and is a good alternative for general anesthesia in adult patients.