Objective:To investigate the safety and efficacy of low molecular weight heparin (LMWH) bridging program in the perioperative period of mini-percutaneous nephrolithotomy (mPCNL) for long-term antithrombotic patients.Methods:The clinical data of 50 patients who received long-term antithrombotic therapy with mPCNL in Sun Yat-sen Memorial Hospital from January 2013 to December 2017 were retrospectively analyzed. Perioperative anticoagulation plans were drawn up after discussion with an internist. Patients with high thrombosis risk were bridged with LMWH during the perioperative period. Resumed LMWH anticoagulation within 48 hours after surgery. Patients with low or medium thrombosis risk directly discontinued anticoagulation one week before surgery. Preoperative anticoagulation was resumed within 48 hours after removing the nephrostomy tube in all patients. We analyzed the general information before surgery, data during surgery, postoperative hemoglobin changes and stone-free rate (SRF) of all cases. 21 patients were treated with LMWH bridging (bridging group), and 29 patients were directly discontinued with anticoagulant drugs (non-bridging group). There was no statistical difference between the two groups in age [(59.7±7.1) vs. (52.4±10.4)years] , gender [(male/female), 14/7 vs. 19/10], BMI [ (24.3±3.9) kg/m 2 vs. (24.7±5.1) kg/m 2], S. T.O.N.E. score (7.4±1.1 vs. 6.9±1.0), stone surface area [ 314.0(31.4-1 130.4) mm 2 vs. 282.5(64.7-866.0) mm 2], the number of calculi involved in calyces (6/15 vs. 13/16) and stone-related surgical history [ 34% (7/21) vs. 24% (7/29) ]. Results:In the bridging group, 18 patients (86%) performed single-channel mPCNL, 3 patients (14%) underwent dual-channel mPCNL, and the operation time was 80 (35-180) min. In the non-bridging group, 27 patients (93%) underwent single-channel mPCNL, 2 patients (7%) performed dual-channel mPCNL, and the operation time was 80 (30-60) min. The mean changes in hemoglobin in the bridging group and the non-bridging group was 18 (-2 -66) g/L and 14 (-25-64) g/L, respectively ( P = 0.073). The average postoperative hospital stay in the bridging group was (8.6 ± 3.5) days, and the non-bridging group was (7.1 ± 2.3) days ( P= 0.057). Two patients in each group received blood transfusion, and no patients received interventional embolization. The SRF of bridging group and non-bridging group was 81.0% (17/21) vs. 75.9% (22/29) ( P = 0.67) 1 month after the operation. During the perioperative period, no patients had thrombotic complications. Conclusions:When mPCNL was required for long-term antithrombotic treatment patients, the use of LWMH alternatives during the perioperative period did not increase bleeding related complications.