Objective To screen the high specific and sensitive monitoring indications in the diagnosis of intestinal barrier dysfunction.Methods A total of 70 critical patients with intestinal barrier dysfunction and acute physiology and chronic health evaluation (APACHE) Ⅱ score≥8 and over the same period 41 patients without intestinal barrier dysfunction and APACHE Ⅱ score≤6 were recruited.The general information,histories,symptoms,physical signs,24 hours urine output and the condition of mechanical ventilation treatment were recorded.The venous blood was taken for bacteria culture,white blood cell counting,creatinine level,diamine oxidase (DAO) activity,D-lactic acid,intestinal fatty acid binding protein (IFABP) and endotoxin level testing.The urine was taken for urinary IFABP level testing.Twenty-four hours urine was reserved for 24 hours total urinary IFABP testing.The factors which might influence intestinal barrier dysfunction were analyzed by univariate analysis and multivariate analysis.The measurement data were analyzed by t test and the count data were analyzed by x2 test.The factors were screened according to receiver operating characteristic (ROC) curve.Results The factors related with intestinal barrier dysfunction were white blood cell counting (OR=3.971,P=0.046),plasma endotoxin level (OR=7.857,P=0.005)and 24 hours total urinary IFABP (OR=11.154,P=0.001).The areas under the ROC curve (AUC)of plasma endotoxin level and 24 hours total urinary IFABP were 0.852 and 0.820 respectively (both P＜0.01).The critical value was 8.0 pg/ml and 17.12 ng respectively.The sensitivity was 97.8％ and 84.4％.The specificity was 66.7％ and 72.7％.Conclusion Once critical patients presented certain gastrointestinal symptoms and physical signs with plasma endotoxin level ＞8.0 pg/ml and or 24 hours total urinary IFABP ＞17.12 ng,which might indicate intestinal barrier dysfunction.