Objective: the objective of this study was to evaluate the accuracy of lung ultrasound in the diagnosis of pneumonia in critically ill patients admitted to the intensive care unit. Methods: This was an observational study conducted between March 2019 and February 2020 on patients older than 18 years who had symptoms associated with ventilator-associated pneumonia after 48 hours from admission to ICU. All patients were subjected to lung ultrasound examination by an intensive care physician who was not involved in the management of the patients. The final ICU diagnosis was the gold standard and was compared to the lung ultrasound diagnosis. Results: Among 108 patients included in this study 37 of them were confirmed to have pneumonia by the ICU team. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of lung ultrasound in the diagnosis of pneumonia in the intensive care unit were 94.87 %, 98.55 %, 97.37 %, 97.14 %, and 97.22%. Conclusion: lung ultrasound can be used with high accuracy in the diagnosis of ventilator-associated pneumonia.