Large cell lung cancer is a histopathologic type of lung cancer, belonging to undifferentiated non-small cell carcinoma, which is less common in clinic. Lung cancer can be divided into non-small cell carcinoma and small cell carcinoma according to histopathologic classification, where non-small cell carcinoma is further divided into squamous epithelial cell carcinoma, adenocarcinoma, large cell carcinoma and other types. Large cell lung cancer accounts for less than 10% of lung cancers, and generally presents with metastasis earlier, with less chance of surgical resection. Because large cell lung cancer lacks the immunophenotypic and histologic features of small cell, adenocarcinoma, or squamous epithelial cell carcinoma, surgical removal of the tumor is required to confirm the diagnosis pathologically, and small biopsies or cytology specimens are also indicated. If large cell lung cancer is diagnosed, it is recommended to actively cooperate with doctors for treatment.