Objective To evaluate the safety of tubeless micro-percutaneous nephrolithotomy (MPCNL). Methods Forty patients who met the criteria(single percutaneous tract, no serious bleeding or perforation in the collecting system and absence of insignificant residual fragments under B-US)were included. After the operation of stone fragmentation, all patients were randomly divided into 2 groups. Twenty patients underwent standard MPCNL(group A), 16 eases had stones in kidney and 4 in upper ureter. Longitudinal sizes of calculi were 1.3-8. 6 era(mean 3.4 era). Twenty patients in group B were with tubeless procedures, 14 patients had stones in kidney and 6 in upper ureter. Longi-tudinal sizes of calculi were 1.1-7. 9 era(mean 3.1 era). Double J stents were placed in all eases. Changes of hemoglobins, pain and complications were recorded and ststistieally analyzed. Results There were no differences in stone size(P=0. 23), operation time (98±29 rain vs 92±31 min, P=0. 63) between the 2 groups. The changes of hemoglobin had no significant difference between 2 groups[(3.3±1.6)% vs (3.1±1.6)%, P=0. 49]. Postoperative pain was assessed using a visual analog scale. The scores of both groups on the first postoperative day were 3.6±1.8(group A) and 3.3±1.5(group B,P=0. 66). On the third day the scores were 1.6±1.2 and 1.8±1.3(P=0. 62). Both groups had 1 patient suffered from mild fever. No transfuaion was performed and no renal colic happened in 2 groups. Conclustion Under certain circumstance, tubeless MPCNL is a safe procedure for patients with urolithiasis.