The choice of antibiotics for pulmonary infections is best when appropriate, and there is no such thing as the best antibiotic. In general, pulmonary infections are divided into community-acquired infections and hospital-acquired infections. The so-called community-acquired infections are lung infections that patients contract outside the hospital; hospital-acquired infections are lung infections that patients contract inside the hospital, and there are certain differences between the two. Community-acquired pneumonia, generally with Gram-positive bacteria and mycoplasma, etc., is common. For common community-acquired pneumonia, penicillins and cephalosporins plus β-lactams are the most used antibiotics with good efficacy, such as piperacillin sulbactam. For mycoplasma infections, moxifloxacin is now the most efficacious. In the case of hospital-acquired infections, there is a high probability of infection with gram-negative bacteria, requiring the application of cephalosporin antibiotics, such as cefoperazone-sulbactam, or more advanced carbapenem antibiotics, such as meropenem and imipenem. With specific infections, such as those of gram-positive cocci, drugs against positive bacteria such as linezolid and vancomycin can be used.