Ventilator-associated pneumonia (VAP) is a common and serious nosocomial infection in mechanically ventilated patients and results in high mortality, prolonged intensive care unit- (ICU) and hospital-length of stay and increased costs. In order to reduce its incidence, it is imperative to better understand the involved mechanisms and to identify the source of infection. The role of the endotracheal tube (ET) in VAP pathogenesis became more prominent over the last decades, along with extensive research dedicated to medical device-related infections and biofilms. ET biofilm formation is an early and constant process in intubated patients. New data regarding its temporal dynamics, composition, germ identification and consequences enhance knowledge about VAP occurrence, microbiology, treatment response and recurrence.This paper presents a structured analysis of the medical literature to date, in order to outline the role of ET biofilm in VAP pathogenesis and to review recommended methods to identify ET biofilm microorganisms and to prevent or decrease VAP incidence.