The treatment course of colon cancer lung metastasis is until the lesion cannot be controlled or the patient cannot tolerate the treatment. Lung metastasis of colon cancer belongs to the advanced stage, and clinically it is considered to be unable to achieve complete eradication, so the treatment of patients should be maintained until the lesion cannot be controlled or the patient cannot tolerate the treatment. In recent years, the treatment of colon cancer lung metastasis has improved significantly, and the application of targeted and immunotherapy has further improved the survival of patients. Long-term treatment, which is often intolerable to patients, has benefited more patients in recent years through small-dose drug maintenance therapy, which is able to control the progression as well as maintain a good quality of life. Therefore, although the lung metastasis of colon cancer is maintained for a long time, adjusting the therapeutic dosage according to the patient’s condition can enable the patient to maintain a better living condition.