Objective:To assess the safety and feasibility of multiple-tract mini and standard single-tract percutaneous nephrolithoto-my in the treatment of complex renal calculi. Methods:Totally 78 cases of complex renal calculi were treated in our hospital from De-cember 2006 to December 2011. Forty cases were treated with multiple-tract mini percutaneous nephrolithotomy and 38 cases were treated with standard single-tract percutaneous nephrolithotomy. Operative time,hospital stay,one phase stone-free rate,postoperative adjuvant therapy,two phase stone-free rate,amount of bleeding were analyzed and compared. Results:In multi-tract group,operative time was (132.11±12.54) min and hospital stay was (12.32±2.15) d and in single-tract group,operative time was (137.85±16.52) min and hospital stay was (11.45±1.92) d (P=0.09 and P=0.06). One phase stone-free rates in multi-tract group and in single-tract group were 77.5%(31/40) and 52.63%(20/38)(P=0.02). Rate of adjuvant therapy was 20.0%(8/40)in multi-tract group,significantly lower than 44.74%(17/38) in single-tract group(P=0.02). Two phase stone-free rates in multi-tract group and in single-tract group were 92.5%(37/40) and 71.05%(27/38)(P=0.01). Amount of bleeding of two group was (88.3±7.5) ml and (85.6±8.2) ml (P=0.13). Conclusions:Higher successful rate and stone-free rate can be achieved in patients with complex renal calculi treated by mul-tiple-tract mini percutaneous nephrolithotomy than by standard single-tract percutaneous nephrolithotomy.