Lung cancer with mediastinal lymphatic metastasis refers to the occurrence of regional lymph node metastasis from a malignant tumor in the lung, i.e., the presence of cancer cells in the mediastinal lymph nodes. Lung cancer is a malignant tumor of the lungs, which is characterized by continuous growth, invasion of surrounding tissues and metastasis. Tumor cells of lung cancer can be transferred to other organs and tissues for continued growth through lymphatic vessels, blood channels, and implantation. Lymph node metastasis of lung cancer will first occur along the lymphatic channels within the lung tissues and around the lung tissues, and ipsilateral hilar and intrapulmonary lymph node metastasis will appear earlier. When it continues to develop, lymph node metastasis in the ipsilateral mediastinum or contralateral mediastinum can appear. When lung cancer with mediastinal lymphatic metastasis occurs, lung cancer is close to the middle and late stages, it is recommended to seek medical treatment in time and standardize treatment under professional doctor’s guidance, so as to avoid delaying the condition.