Tumor marker CA199 is elevated after lung cancer surgery, first of all, perfect CT, if it is tumor recurrence, surgery and drug treatment may be needed; if it is benign disease, targeted treatment is needed. If CA199 is elevated due to recurrence and metastasis of lung cancer, patients who can be operated will be given surgical resection again, and chemotherapy and other drug treatments will be given after operation. For patients who cannot be operated, targeted drugs or immune drugs should be chosen according to different gene and immune expression. Some patients also need localized treatment such as radiotherapy or intervention. If CA199 is elevated due to inflammatory diseases or benign tumors, anti-inflammatory drugs, such as amoxicillin, can be given, and patients with large tumors can be treated with surgery to remove benign tumors. If tumor marker CA199 is elevated after lung cancer surgery, it is recommended that the patient should consult a hospital for systematic diagnosis and treatment by a professional doctor.