Pneumonia is an infection of the lungs caused by the invasion of viruses, bacteria and other pathogens, often accompanied by cough and fever, while the concept of interstitial pneumonia is relatively new. Although both are pneumonia and both can cause great damage to the lungs, there are significant differences in clinical symptoms, causes, nature of the disease, and treatment modalities. Interstitial pneumonia refers to inflammatory and fibrotic lesions of the interstitial lung that are caused by a variety of factors. At this stage, patients are divided into two types of causes, one with known etiology, including environment, drugs, and diseases, among which environment includes organic dust, inorganic mineral dust, irritating toxic gases, etc.; drugs include interferon, furantoin, amiodarone, etc.; diseases mainly refer to connective tissue diseases or vasculitis, such as systemic sclerosis, polymyositis/dermatomyositis, rheumatoid arthritis, systemic lupus erythematosus, etc. The other type of disease is of unknown etiology, also known as “idiopathic”, with major risk factors such as genetics, age, smoking, environmental exposure, viral infections, and gastroesophageal reflux. Pulmonary fibrosis is a chronic progressive fibrotic interstitial pneumonia of unknown etiology that is confined to the lungs and occurs in middle-aged and older men. Interstitial pneumonia causes irreversible damage to the patient’s lungs. Pneumonia refers to infectious inflammation, mostly caused by various pathogens and other factors, the most common being bacterial pneumonia and viral pneumonia, where patients will have typical symptoms such as fever, cough, and difficulty breathing. There are many causes of pneumonia, but it is mainly caused by external infections. Infectious factors include bacteria, viruses, fungi, atypical pathogens, physical and chemical factors, and diseases are classified due to different infectious factors, such as viral pneumonia, pulmonary fungal disease, etc. For common viral pneumonia, the viruses include respiratory syncytial virus, influenza virus, etc.; for bacterial pneumonia, the bacteria include Staphylococcus aureus, Streptococcus pneumoniae, etc. The main causes of its disease triggering are air turbidity, smoking, and impaired immune function. There is no specific treatment for viral pneumonia, while for bacterial pneumonia, appropriate antibiotics such as cephalosporins and carbapenems need to be selected according to the pathogenic bacteria. The first difference is in the nature of the disease: pneumonia is an inflammatory phenomenon of the lungs caused by external germs and other infections, which is contagious and occurs in people with poor health and low immunity; interstitial pneumonia is a diffuse interstitial fibrosis pneumonia that occurs mostly in people over 40 years of age. The second is in the etiology, pneumonia is mainly due to viral infections, bacterial infections or their own respiratory diseases, bacterial infections are mainly Streptococcus pneumoniae, Streptococcus staphylococcal infection, special pathogens are mycoplasma, chlamydia, Legionella infection. For those who have respiratory diseases if not treated in time can also cause pneumonia; interstitial pneumonia is also affected by viral infections, but also by air pollution, and even by diseases, drugs, etc., such as chronic pneumonia, hereditary pulmonary fibrosis, etc. Modern medicine does not have too good treatment for interstitial lung fibrosis except lung transplantation. The side effects of treatment such as hormones are high. Many other new drugs are in the experimental stage. Obeticholic acid, doxycycline, and nicorandil have all been reported to have some efficacy in interstitial pulmonary fibrosis. Among them, doxycycline is a cost-effective antibiotic, obeticholic acid for liver fibrosis, and nicorandil for myocardial ischemic disease. Nowadays, oral administration of compound salvia drops, erythromycin, and acetylcysteine can play a role in preventing exacerbation of pulmonary fibrosis. In general, both interstitial pneumonia and pneumonia are just a generic term, while pneumonia tends to be more pathologically described, neither refers to the disease, and in simple terms they refer to different stages of development of the same disease. When interstitial pneumonia develops, inflammatory fluid exudes from the interstitial space of the lungs, which is like a sponge filled with water, preventing oxygen from entering the alveoli, thus preventing the body from providing sufficient oxygen and causing breathing difficulties.