This single-center retrospective study examined patients who underwent elective surgery under general anesthesia at Hiroshima University Hospital from April 2016 to March 2023. The study evaluated postextubation pneumonia (PEP), defined as pneumonia diagnosed within 30 days after extubation with newly started antibiotic treatment. Among 31,828 eligible patients, 212 developed PEP, and PEP occurred more often than ventilator-associated pneumonia. The study concluded that PEP is a clinically important complication associated with factors such as advanced age, male sex, low BMI, impaired consciousness, reduced ADL, and several surgical sites.