Ventilator-associated pneumonia or known as VAP is known to be the most prevalent and lethal nosocomial infection in critical care that occurred after 48 hours of endotracheal intubation. Mostly patients may have already been extubated by the time VAP started. It can be treated by antibiotics according to the early or late onset of the infection. Head of bed elevation, dental care with chlorhexidine, stress ulcer prophylaxis, deep venous thrombosis prophylaxis, daily sedation evaluation, and spontaneous breathing trials are all included in the five-part Institute of Healthcare Improvement (IHI) VAP bundle, and are thought to be able to prevent VAP. This study aims to review past literature and studies regarding ventilator associated pneumonia.