This study aims to systematically evaluate the safety and efficacy of different early urinary catheter removal strategies following radical resection of mid-low rectal cancer. Current clinical practice faces controversy regarding the optimal timing of catheter removal (24 hours vs. 48 hours) and lacks precise preventive measures for patients at high risk of postoperative acute urinary retention (AUR). To address these issues, this study is designed as a three-arm randomized controlled trial, directly comparing three management protocols: catheter removal at 24 hours postoperatively, catheter removal at 48 hours postoperatively, and an individualized strategy guided by a predictive model (i.e., preventive administration of tamsulosin to high-risk AUR patients prior to catheter removal). The primary endpoint is the rate of recatheterization within 7 days after the initial removal, with secondary endpoints comprehensively assessing urinary tract infections, voiding function, and postoperative complications. The ultimate goal is to provide high-quality evidence-based medical evidence to establish a precise and standardized clinical pathway for individualized postoperative catheter management.