Objective To evaluate the feasibility,safety and efficacy of tubeless percutaneous nephrolithotomy ( PCNL).Methods Patients who underwent PCNL were randomized into 2 groups by extracting a random number generated from random number table,tubeless PCNL group and traditional PCNL group when the stones were cleared.Each patient in tubeless PCNL group was treated with insertion of a F5 ureteral double pigtail stent without placement of nephrostomy tube,while both double pigtail stent and F16 nephrostomy tube were placed in patients in traditional PCNL group.Exclusion criteria were severe bleeding requiring blood transfusion,stone residual requring a second PCNL,severe hydronephrosis with the thickness of renal parenchyma less than 5 mm,pyonephrosis,stricture of ureter or ureteropelvic junction,and severe perforation of the collecting system.A total of 50 patients were enrolled in this study.Tubeless PCNL and traditional PNCL were performed in 25 patients,including 27 kidney units,respectively.The two groups had comparable demographic data.All the operations were performed by the same surgeon.Evaluation factors included postoperative pain,decreased hemoglobin,blood transfusion rate,incidence of fever and perirenal hematoma,and duration of hospitalization.Results The average visual analogue scale (VAS) score on postoperative day 1 in tubeless PCNL group was 2.24 compared with 5.04 in traditional PCNL group (P ＜ 0.01 ).The average hospital stay in tubeless PC NL group (3.04 d) was significantly shorter than that in traditioal PCNL group (6.88 d) (P ＜0.01 ).The differences in average hemoglobin drop and stone clearance in the 2 groups were not significant.The differences between the 2 groups in blood transfusion ( 1/25 in tubeless PCNL group vs 3/25 in traditional PCNL group,P ＞0.05),renal hematomas rate (6/27 in tubeless PCNL group vs 7/27 in traditional PCNL group,P ＞ 0.05) and fever rate (3/25 in tubeless PCNL group vs 4/25 in traditional PCNL group,P ＞0.05 ) were not significant.There was no incidence of urinary leakage from the nephrostomy site in the 2 groups.Conclusions Tubeless PCNL can significantly decrease postoperative pain and discomfort and shorten the duration of hospitalization without increase of complications.Tubeless PCNL is safe,effective and performable,but the contraindications such as massive haemorrhage,pyonephrosis,ureteral obstruction,severe perforation of the collecting system,residual stone requring a second PCNL,should be kept in mind.