Aim: to enhance the effectiveness of surgical treatment for benign rectal tumors by optimizing transanal endoscopic microsurgery (TEM). Materials and methods. From 2007 to 2024, a total of 153 patients with benign rectal tumors underwent TEM. The cohort comprised 80 men and 73 women, aged between 37 and 76 years, with a mean age of 58,4±11,7 years. Based on the surgical method, the patients were divided into two groups. The first group included 75 patients who underwent traditional TEM tumor resection. The second group consisted of 78 patients who underwent surgery using an advanced TEM technique. This approach involved preoperative marking of the mucous membrane surrounding the tumor, utilizing endoscopic refinement methods within healthy tissues. The effectiveness of the procedure was assessed through morphological examination of the excised tumors and the analysis of recurrence rates. Results. In the first group, en-bloc tumor resection was performed on 62 patients (82.6%), while fragmentation resection was conducted on 13 patients (17.4%). Among those who underwent en-bloc resections, R0 (complete resection) was achieved in 59 cases (95.1%), and R1 (incomplete resection) occurred in 3 patients (4.8%). Local recurrence was noted in 11 patients (14.0%). In the second group, en-bloc tumor resection was conducted on 70 patients (89.7%), with fragmentation resection performed on 8 patients (10.3%). For the en-bloc resections in this group, R0 was achieved in 69 cases (98.5%), and R1 was observed in 1 patient (1.5%). Local recurrence was detected in 3 patients (3.8%). Conclusion. Optimizing TEM for benign rectal tumors, which includes preoperative determination of resection margins, improves treatment efficacy by 73.7% compared to conventional techniques. Additionally, this approach significantly reduces recurrence rates from 14.6% to 3.8%.