Background: In the treatment of patients with locally advanced very low rectal cancer, neoadjuvant chemoradiotherapy followed by total mesorectal excision (TME) is considered a standard therapeutic approach. Short-course hypofractionated radiotherapy, in combination with subsequent chemotherapy, has been shown to be comparable to long-term chemoradiotherapy in terms of neoadjuvant therapy effects in rectal cancer. Additionally, it has been observed that hypofractionated radiotherapy, when combined with programmed death L-1 (PD-L1) blockade, can enhance the immune response. This study aims to investigate efficacy and safety of organ preservation in patients with locally advanced very low rectal cancer by utilizing total neoadjuvant therapy involving split-course hypofraction radiotherapy in conjunction with CAPOX and Envafolimab (a humanized single-domain anti-PD-L1 antibody fused to an Fc fragment). Methods: TheTRACE-LE trail is an open-label, single-arm, multicenter, phase II trial. The target sample is 72 participants. Key eligibility criteria include individuals aged 18-75, confirmed rectal adenocarcinoma, cT3-4N0/cT1-4N1-2 with lower margin ≤ 2cm from anorectal ring's upper edge (MRI) and ECOG performance status of 0-2. The treatment protocol include preoperative split-course hypofractionated radiotherapy (5×7Gy), in conjunction with 6 cycles of CAPOX chemotherapy and Enverolimab (300 mg subcutaneous injections) administered in a 3-week treatment cycle. The primary outcome measure is organ preservation, specifically the rectum intact, owing to no radical total mesorectal excision (TME), no locoregional regrowth unless amenable to limited, curative (R0) salvage surgery by local excision (LE) and no permanent stoma (including a never reversed protective stoma, or a stoma owing to toxicities and/or poor functional outcomes). The secondary outcome measures encompass ypT0-1 rate, pathological complete response (pCR) rate, acute and late toxicity as per NCICTCAE V.5.0, local recurrence rate, local regional recurrence rate, disease-free survival, quality of life, and anorectal function. Clinical trial information: NCT05970900.