Precautions in colon cancer surgery are as follows: 1, the principle of tumor-free surgery should be carried out during the surgery, to avoid tumor dissemination caused by the surgery; 2, colon cancer is a large intestine surgery, the large intestine contains a lot of bacteria, and the contamination is more serious, so we should pay attention to the principle of asepsis, do not contaminate the abdominal cavity during the process, once contamination will cause abdominal infection, and even affect the later healing, which is also the principle of tumor-free surgery and asepsis to be paid attention to; 3 Once anastomotic fistula occurs, such patients have abdominal infection. To avoid anastomotic fistula, the surgeon should pay attention to the vascular protection and blood flow protection of the intestinal tube during surgery; because one of the main reasons for anastomotic fistula is poor blood flow, the vascular arch at the edge of the colon should be protected; secondly, to prevent infection, infection is also the cause of fistula, and prevention of anastomotic fistula is also a precaution in colon cancer surgery; 4. During the perioperative period, patients have to protect their heart, brain, lungs and important organs, because tumor patients are prone to hypercoagulable state, especially prone to long thrombosis, so VTE prevention should be performed. In the perioperative period, physical VTE prophylaxis should be performed, including VTE prophylaxis with low-molecular heparin and prevention of thrombosis.