<p>To investigate the effect of preoperative administration of finasteride on intraoperative bleeding during transurethral laser resection of the prostate.&#xa0;We retrospectively analyzed 120 patients who underwent transurethral laser resection of the prostate. Patients were divided into two groups based on whether finasteride was used (<i>n</i> = 60) or not (<i>n</i> = 60). The following parameters were collected: age, height, weight and body mass index (BMI), international prostate symptom score (IPSS), quality of life (QoL) score, prostate-specific antigen (PSA), prostate volume, operation time, hospital stay, continuous bladder irrigation (CBI); catheterization duration, re‐catheterization, preoperative and postoperative hemoglobin concentrations, preoperative and postoperative serum sodium concentrations, postoperative urinary tract infection (UTI) rate, hospitalization costs. We compared the two groups using Student’s t test, Mann–Whitney U test and χ2 test for quantitative and categorical variables, respectively. A linear regression model was employed to identify predictive factors of transurethral laser resection of the prostate.&#xa0;Compared with the non-finasteride group, the finasteride group had a lower bleeding level (Δ Hemoglobin 2.5&#xa0;g/L vs. 7&#xa0;g/L, <i>p</i> = 0.025), and lower hospitalization costs (21.62 thousand Yuan vs. 23.11 thousand Yuan, <i>p</i> = 0.001). In multivariate analyses, the regular use of finasteride (<i>r</i>=-0.304, <i>p</i> = 0.001) was the independent predictive factor of intraoperative bleeding during transurethral laser resection of the prostate.&#xa0;The regular use of finasteride before transurethral laser resection of the prostate helps to reduce intraoperative bleeding level.</p>