Both pneumonia and tuberculosis are infectious diseases, and both can be manifested as hyperdense shadows on chest radiographs. However, there are many differences between pneumonia and tuberculosis: 1. Infectious agents: pneumonia may be caused by S. pneumoniae, Haemophilus influenzae, Klebsiella, etc., while tuberculosis is caused by Mycobacterium tuberculosis, which is a specific infection; 2. Clinical symptoms: pneumonia generally has an acute onset, while tuberculosis is a long-term chronic disease. Pneumonia generally presents with a cough and a large amount of pus sputum, while tuberculosis has relatively little sputum; 3. Imaging manifestations: pneumonia presents with a thin patchy, cloudy hyperdense shadow with blurred borders, which is more common in both lower lungs. Tuberculosis is an aerobic bacterium, so there are special manifestations, mostly in the posterior segment of the upper lobe and the dorsal segment of the lower lobe of both lungs, which is an aerobic manifestation, but tuberculosis is a long-term chronic process, so the lesion manifestation is polymorphic, which can manifest as fresh exudative lesions, proliferative lesions or fibrous calcified lesions; 4. tuberculosis is a long-term chronic treatment process, generally requiring 6-9 months of treatment.