Objective To analyze the serum levels of soluble intercellular adhesion molecule-1(sICAM-1),toll like receptor 4(TLR4)and haptoglobin(HPT)in patients with severe cerebral infarction complicated by nosocomial infection and their clinical value.Methods A total of 80 patients with severe cerebral infarction who visited the hospital from September 2019 to December 2023 were selected as the study group,and were separated into an infection group(29 cases)and a non infection group(51 cases)based on whether the pa-tients had nosocomial infection.92 healthy individuals who underwent physical examination in the hospital were selected as the health group.Enzyme linked immunosorbent assay(ELISA)was applied to detect serum levels of sICAM-1,TLR4,and HPT in each group,and clinical data of infection group and non infection group were analyzed.Pearson method was applied to analyze the correlation between serum sICAM-1,TLR4,and HPT levels in patients with severe cerebral infarction complicated by nosocomial infection.Multivariate Logis-tic regression was applied to analyze the factors affecting the occurrence of nosocomial infection in patients with severe cerebral infarction.Receiver operating characteristic(ROC)curve was applied to evaluate the di-agnostic value of serum sICAM-1,TLR4,and HPT levels for the occurrence of nosocomial infection in patients with severe cerebral infarction.Results Compared with the health group,the serum levels of sICAM-1,TLR4,and HPT in the study group were all elevated,and the differences were statistically significant(P＜0.05).Compared with health group,serum sICAM-1,TLR4 and HPT levels in the non infection group and the infection group were increased,and the differences were statistically significant(P＜0.05).Compared with the non infection group,the serum levels of sICAM-1,TLR4,and HPT in the infection group were all elevated,and the differences were statistically significant(P＜0.05).The serum sICAM-1 was positively correlated with TLR4 and HPT levels,and TLR4 was positively correlated with HPT in patients with severe cerebral in-farction complicated by nosocomial infection(r=0.473,0.529,0.421,P＜0.001).There were significant differences between the infection group and the non infection group in the presence or absence of diabetes and smoking history(P＜0.05).Diabetes,smoking history,serum sICAM-1,TLR4,and HPT levels were the in-fluencing factors of nosocomial infection in patients with severe cerebral infarction(P＜0.05).The area under the curve(AUC)of combined diagnosis of serum sICAM-1,TLR4,and HPT for nosocomial infection in pa-tients with severe cerebral infarction was 0.991,with sensitivity of 96.55％,and specificity of 94.12％,which were superior to those of the individual diagnosis of sICAM-1,TLR4,and HPT(Z combined diagnosis-SICAM-1=1.972,P=0.049,Z combined diagnosis-TLR4=3.068,P=0.002,Z combined diagnosis-HPT=2.337,P=0.020).Conclusion The serum levels of sICAM-1,TLR4,and HPT are all elevated in patients with severe cerebral infarction complicated by nosocomial infection.The combined detection of the three has high clinical diagnostic value for the occurrence of nosocomial infection in patients with severe cerebral infarction.