Metastasis is a unique biological behavior characteristic of malignant tumors, and the cranial brain is one of the four sites where lung cancer is most likely to metastasize. In clinical practice, when a patient develops headache, for lung cancer patients, the first consideration is whether there is a possibility of cranio-cerebral metastasis. For such patients, detailed medical history should be taken to determine whether the patient also has headache, dizziness, lightheadedness, and some patients also have nausea, jet vomiting, visual field deficit, and motor or sensory impairment. If the patient has these manifestations, the patient is more likely to have intracranial metastasis. In the treatment of this part of patients, magnetic resonance examination is performed first to further clarify the possibility of cranial metastasis of the tumor.