Background: Intercellular Adhesion Molecule-1 (ICAM- 1), which mediates cell-cell adhesion to the extracellular matrix, may be released in cascades throughout sepsis, causing serious damage to vascular endothelial cells. Numerous investigations have demonstrated that it is elevated in individuals with sepsis. Thus, ICAM-1 may be a useful biomarker in predicting and diagnosing sepsis. Objectives:The aim of the current work was to measure serum sICAM-1 level in septic ICU patients to determine the association between serum sICAM-1 and inflammatory response of sepsis, clinical severity and mortality. Patients and Methods: A Cohort study was conducted on 40 critically ill patients with sepsis and admitted to the intensive care unit in the Internal Medicine Hospital, Zagazig University Hospitals. Results: There was a high significant increase of SICAM-1 level in septic patients with MOF group compared to patients without MOF (p=0.003). A significant increase of serum ICAM-1 level in the non-survivors group compared to the survivor's group (p < 0.001). Serum ICAM-1 had a significant positive correlation with age, APACHE II, SOFA score, TLC, ESR, CRP, urea and creatinine. There was no correlation between serum ICAM-1 with each sex, AST and ALT. Using multivariate regression analysis, it was found that serum sICAM-1 level is an independent factor for predicting the severity. Serum ICAM-1level at 232.4 ng/ml had a sensitivity of 100%, specificity of 100%, 100% NPV and 100% PPV in detecting the clinical Outcome of septic patients in ICU. Conclusions: It could be concluded that the increased serum level of sICAM-1 in septic ICU patients is associated with inflammatory response and organ damage and may predict their clinical Outcome during their admissions in ICU.