Lung squamous cell carcinoma with intratracheal diffuse leukoplakia as the main manifestation is very rare in clinic. The clinical data of a patient with pulmonary squamous cell carcinoma with intratracheal diffuse leukoplakia admitted to the Affiliated Hospital of Jining Medical University in December 25, 2021 were retrospectively analyzed in order to improve the understanding of this special manifestation. The patient was a 73-year-old male with clinical manifestations of cough, sputum, and blood-stained sputum. Chest CT indicated patchy high-density shadow on the upper right lung, whole-course thickening of trachea and bronchial walls, and bronchoscopy showed diffuse trachea-bronchial mucosa congestion and edema, with a large number of leukoplakia on the surface. The clinical effect was stable after 2 cycles of chemotherapy. Lung squamous cell carcinoma accompanied by diffuse leukoplakia in the trachea is a rare presentation. Chest CT can show thickening of the tracheal and bronchial wall, while the lesion and tumor signs of the primary lesion are not obvious. Electronic bronchoscopy as soon as possible can avoid missed diagnosis.