Subpleural nodules may be malignant, such as metastatic or primary adenocarcinoma, or benign, such as tuberculosis, etc. A puncture biopsy may be performed to accurately determine the nature of the nodule. Subpleural nodule refers to a lung nodule located under the pleura, which may also be accompanied by thickening of the adjacent pleura. It has many causes, including malignant nodules such as metastatic or primary adenocarcinoma, squamous carcinoma, small cell tumor, etc., of which adenocarcinoma has the highest incidence, and benign nodules such as inflammation, fungal infection, and tuberculosis. The impact of subpleural nodules on lung function is relatively small, and most of them have no obvious clinical manifestations and are only found during routine physical examination. Some malignant or infectious lesions may manifest as fever, cough, sputum and blood in sputum, hemoptysis and chest pain. Imaging examination has some limitations in its qualitative diagnosis, and its diagnosis mostly relies on CT-guided diagnostic nodule puncture biopsy. It is recommended to go to the hospital in time for diagnosis of subpleural nodules.