To evaluate the effectiveness of poloxamer-based thermo-sensitive sol-gel instillation after transurethral resection of the prostate (TURP) for preventing a urethral stricture.A total of 198 patients underwent TURP for benign prostatic hyperplasia. Recruited patients were randomly divided into two groups: Groups A and B. Patients in group A (100 patients, experimental group) received poloxamer-based thermo-sensitive sol-gel instillation, and patients in the group B (98 patients, control group) received lubricant instillation after TURP. Each patient was evaluated at 4 weeks (V1), 12 weeks (V2), and 24 weeks (V3) after the surgery. The effectiveness of poloxamer-based thermo-sensitive sol-gel instillation was evaluated based on the International Prostate Symptom Score (IPSS)-Quality of Life (QoL), Overactive bladder questionnaire (OAB-q), peak urine flow rate (Qmax), postvoid residual volume (PVR), and cystoscopy.Among 198 initial participants, 80 patients in group A and 83 patients in group B had completed the experiment. There were no significant differences in IPSS-QoL and OAB-q between groups. However, Qmax (mL/sec) showed significant difference between group A and group B (18.92±9.98 vs. 15.58±9.24, p=0.028) at 24 weeks after surgery. On cystoscopic examination, urethral stricture after TURP was observed in 2 of 80 subjects in group A and 10 of 83 subjects in group B (p=0.023).Poloxamer-based thermo-sensitive sol-gel instillation after TURP decreased the incidence of urethral stricture. This article is protected by copyright. All rights reserved.