The clinical manifestation of a dry cough without fever or cold is mainly seen in non-infectious inflammatory reactions of the respiratory system. For example, wheezing chronic bronchitis, cough variant asthma, and eosinophilic pneumonia due to allergic factors. It is also seen as a result of occupying lesions, such as diffuse fibrosis of the interstitial lung, varying degrees of bronchiectasis, obstructive emphysema, and pulmonary heart disease. Malignant tumors of the lung, such as bronchopulmonary carcinoma and alveolar cell carcinoma, may also present with the above clinical symptoms, as well as silicosis and pneumoconiosis.