Abstract: Linezolid is a widely used anti-Gram-positive bacteria drug. This article summarizes the main changes in the pharmacokinetics of linezolid in critically ill patients, and to provide reference for the rational use of linezolid in critically ill patients. The absorption and distribution of linezolid in critically ill patients do not change significantly; hepatic insufficiency, abnormal renal function, renal replacement therapy and extracorporeal membrane oxygenation can affect the clearance rate of linezolid and cause changes in the therapeutic concentration, thereby affecting the therapeutic effect. It is recommended to implement therapeutic drug monitoring and keep the trough concentration at 2-8 mg·L^-1 to ensure the best efficacy and safety when linezolid is used in critically ill patients.