Percutaneous nephrolithotomy (PCNL) in the prone position has been considered the treatment of choice for large kidney calculi, however, supine (PCNL) can be used as an alternative management procedure. We compare both procedures in the management of renal stones. Since June 2009 to March 2011, 60 consecutive PCNL were performed at Benha university hospital, group (A) 30 patients in prone position, and group (B) 30 patients in supine position .The mean operative time in prone group was 76.8 ± 16.6 min. while in supine group was 55.43± 22.5 min. The stone free rate in prone group was 86.7% and in supine group was 83.3%.The blood loss required blood transfusion in prone group was 10% and in supine group was 6.7%. The intra-operative morbidity of prone group was 16.7% and in supine group was 10%.The postoperative morbidity of prone group was 20% and in supine group was 23.3%. The mean hospital stay of prone group was 3.87 ± 2.77 days, and in supine group was 3.33 ± 2.12 days with no statistically significant differences between both groups. PCNL in supine position is safe, effective and suitable for all patients.