Capillary leak syndrome(CLS) in critically ill patients is common,and the clinical manifestations of CLS include systemic edema,hypoproteinemia,effective circulating blood volume reduction and blood concentrated.The common pathogenesy is sepsis,severe trauma,cardiopulmonary bypass and so on.CLS is divided into leakage period and recovery period usually.Clinical manifestation and treatment in different period are different in each pathophysiologic process.Although the methods of treatment are more,effective treatment measures are in shortage.More therapeutic measures are studied currently which include improvement of endothelial cell function,macromolecular colloidal solution application,continuous blood purification and so on.It is a guiding value to understand the pathological mechanism,clinical manifestations,diagnosis and treatment of the CLS. Capillary leak syndrome (CLS) in critically ill patients is common, and the clinical manifestations of CLS include systemic edema, hypoproteinemia, effective circulating blood volume reduction and blood concentrated. The common pathogenesy is sepsis, severe trauma, cardiopulmonary bypass and so on. CLS is divided into leakage period and recovery period usually. Clinical monitoring and treatment in different periods are different in each pathophysiologic process. Although the methods of treatment are more, effective treatment measures are in shortage. cell function, macromolecular colloidal solution application, continuous blood purification and so on. It is a guiding value to understand the pathological mechanism, clinical manifestations, diagnosis and treatment of the CLS.