On the basis of our previous study, this project further explored whether patients with effective neoadjuvant chemotherapy can obtain a higher organ preservation rate after total neoadjuvant therapy. This study was designed to enroll patients with low and intermediate-risk rectal cancer. After 2 cycles of XELOX chemotherapy, patients with effective chemotherapy as judged by high-definition MRI of the rectum (the long diameter of the tumor was shortened by ≥30% compared with that before treatment) were randomly divided into two groups. One group was long-course chemoradiotherapy combined with consolidation chemotherapy (TNT group). In the other group, long-term chemoradiotherapy combined with immunotherapy and consolidation chemotherapy (iTNT group), we explored whether TNT could achieve a higher organ preservation rate after effective neoadjuvant chemotherapy in patients with low and intermediate-risk low rectal cancer, and the organ preservation rate of TNT combined with immunotherapy.