Summary: Introduction: Endoscopic submucosal dissection (ESD) is an endoscopic treatment method for the removal of neoplastic lesions of the digestive tract. Thanks to this technique, we can achieve complete (en bloc) R0 endoscopic resection of even large lesions in one piece. We thereby obtain a valuable resection for further histopathological evaluation and, with a suitably chosen lesion, achieve a curative resection. Methods: Retrospective analysis of our file in the period 1/2020–01/2023. The primary objective was to determine how endoscopic evaluation and selection of included rectal lesions treated with the ESD technique correlates with histopathological results. The secondary objective was to determine the curability of the treatment we performed in our group of patients. We included lesions over 20 mm with the assumption of maximum invasion into the surface parts of the submucosa, i.e., JNET 2B. In addition, we included recurrent lesions in the scar after previous endoscopic or surgical treatment, submucosal lesions up to 20 mm and lesions smaller than 20 mm, especially in the lower rectum, which cannot be radically removed en bloc by loop-based techniques. Results: We included a total of 76 rectal lesions. JNET 2B lesions were 59 of them (77.6%). The most common histopathological diagnosis was high-grade dysplasia (HGD) in 35 (46%) cases. We achieved curative endoscopic resection in the majority (93.4%) of patients. Five patients (5.26%) required subsequent surgical or oncological therapy after ESD and further staging. Conclusion: The results of our work confirm the effectiveness of ESD as a therapeutic method suitable for achieving en bloc R0 resection of rectal lesions and thus their correct histopathological evaluation. However, the correct selection of patients remains crucial. Key words: endoscopic submucosa dissection – rectal lesions – curative resection