Purpose: The present study evaluates the efficiency and reliability of a hemostatic agent ABS (Ankaferd Blood Stopper®) in tubeless percutaneous nephrolithotomy (PCNL). Patients and Methods: A total of 90 patients were divided into two subgroups. The first group had ABS applied during the intervention, whereas the control group underwent regular tubeless PCNL in this prospective randomized study. Age, stone size, operative time, postoperative hemoglobin change, renal parenchyma thickness, postoperative ureteral catheter removal time, access number, nephroscope time, blood transfusion rate, serum creatinine change, complication rate, visual analogue scale (VAS), and hospitalization time were compared between the two groups. Results: Preoperative and postoperative data obtained from both groups were compared. No statistically meaningful differences were found related to variables of mean age, stone size, access number, serum creatinine change, operative time, renal parenchyma thickness, VAS scores, and hospitalization period. Whereas the nephroscope time (minutes) was longer in the ABS group (Group 1 [G1]:3, 33±1, 72 vs G2:2, 62±1, 43, P=0.035), hemoglobin (Hb) decrease, and urine clarity time were statistically lower compared with the control group. Hb decrease was (mg/dL) (G1: 1.40±1.04 vs G2: 1.84±1.15, P=0.034), and urine clarity time was (hour) (G1: 9.60±5.50 vs G2: 11.95±4.71, P=0.012), respectively. Complications were encountered in three (6.6%) patients of the ABS group and in four (8.8%) of the control group. Conclusion: ABS is an efficient and reliable hemostatic agent in tubeless PCNL. Comparative studies are needed, however, with other hemostatic agents that might be applied in tubeless PCNL. © Mary Ann Liebert, Inc.