Hemoptysis in advanced colon cancer patients may be caused by the metastasis of colon tumor to lung, because the advanced stage of colon cancer means that the tumor has metastasized distantly, including liver metastasis, lung metastasis, bone metastasis, and even peritoneal metastasis. If hemoptysis occurs, it is more likely to be caused by lung metastasis due to colon cancer. To make a definite diagnosis, CT scan of chest and abdomen should be performed to clarify whether the tumor has lung metastasis, and to clarify the size, number and location of the lung metastasis. If the hemoptysis is caused by lung metastasis, active treatment is needed to stop the bleeding and prevent the patient from dying due to hemorrhage, and also to treat the tumor, such as using targeted drugs and chemotherapy drugs.