Objective: To investigate the expression and significance of plasma endotoxin in patients with bacterial infection in intensive care unit. Methods: Ninety-seven patients with bacterial infections treated in Zhoukou Central Hospital from January 2016 to February 2018 were selected. The patients were divided into 3 groups: 29 patients with sepsis were in group A, 38 severe sepsis in group B, and 30 septic shock in group C. The clinical data were analyzed and the levels of endotoxin in each group were detected. Results: The level of endotoxin was (1.01±0.12) EU/mL, APACHE IIV was 32.49±5.11, and SOFA scores was 12.06±2.03 in group C, which were significantly higher than those in group A and B (P<0.05); there was no significant difference in bacterial distribution between each group (P>0.05). The level of endotoxin in patients with gram negative bacteria was (0.98±0.11) EU/mL, which was significantly higher than that of Gram-positive bacteria (P<0.05); endotoxin were positively correlated with APACHE II score and SOFA score (r=0.455, 0.460; P<0.05); the level of endotoxin in the dead patients was (1.11±0.18) EU/mL, which was significantly higher than that in the surviving patients (P<0.05). Conclusion: The level of plasma endotoxin in patients with bacterial infection in intensive care unit is related to the type of bacteria, and helps to judge the severity and prognosis of patients.