Abstract: The nuclear protein of the testis (NUT) midline carcinoma is a highly aggressive malignant epithelial neoplasm. The tumor is characterized by chromosome rearrangement of the NUT gene on 15q14, which results in the expression of NUT protein outside the testis. Pathologically, the tumor is an undifferentiated carcinoma with focal squamous differentiation. The NUT midline carcinoma can occur in multiple parts of the body, most of which happen in the midline structure of the head and neck and the mediastinum. Pulmonary cases are unusual and rarely recorded. However, the clinical course of primary lung NUT midline carcinoma is abnormally rapid and dangerous, and the diagnostic characteristics are still unclear. Therefore, this paper mainly discusses the clinical diagnosis and treatment of primary lung NUT midline carcinoma.