Objective To observe the dynamic changes in serum levels of IL-6， IL-8， TREM-1， uPAR， and presepsin in patients with septic shock and to analyze the diagnostic significance of these biomarkers. Methods A total of 150 sepsis patients admitted to the hospital between February 2023 and February 2025 were prospectively enrolled as study subjects. According to their clinical conditions， the participants were categorized into a sepsis group （non-shock， n = 44） and a septic shock group （n = 106）. Additionally， 30 healthy individuals with normal clinical indicators during the same period were selected as the control group. The serum levels of IL-6， IL-8， TREM-1， uPAR， and presepsin were measured and compared across the different groups. Spearman correlation analysis and logistic regression analysis were conducted to assess the association between these biomarkers and the severity of sepsis. The diagnostic performance of these biomarkers for septic shock was evaluated using receiver operating characteristic （ROC） curve analysis. Results There were statistically significant differences in serum levels of IL-6， IL-8， TREM1， uPAR， and presepsin among the different groups （P < 0.05）， with the highest values observed in the septic shock group， followed by the sepsis group and the control group （P < 0.05）. The APACHE Ⅱ and SOFA scores of patients with septic shock were significantly higher than those of patients with sepsis （P < 0.05）. Spearman correlation analysis revealed that serum concentrations of IL-6， IL-8， TREM1， uPAR， and presepsin were positively correlated with both APACHE Ⅱ and SOFA scores， with correlation coefficients （rs） of 0.758， 0.880， 0.837， 0.832， and 0.846 for APACHE Ⅱ score， and 0.487， 0.549， 0.557， 0.626， and 0.664 for SOFA score， respectively （P < 0.05）. Logistic regression analysis indicated that serum levels of IL-6 （OR = 1.055）， IL-8 （OR = 1.054）， TREM1 （OR = 1.038）， uPAR （OR = 1.010）， and presepsin （OR = 2.103） were significantly associated with the development of septic shock （P < 0.05）. ROC curve analysis demonstrated that the AUC values for serum IL-6， IL-8， TREM1， uPAR， and presepsin in diagnosing septic shock were 0.608， 0.724， 0.887， 0.848， and 0.885， with corresponding sensitivities of 0.432， 0.909， 0.795， 0.909， and 0.591， and specificities of 0.880， 0.481， 0.915， 0.736， and 0.977， respectively. When these biomarkers were combined， the AUC increased to 0.973， with a sensitivity of 0.943 and a specificity of 0.953. Furthermore， the AUC for presepsin alone was significantly higher than that for IL-6 and IL-8 alone （P < 0.05）. Additionally， the AUC for the combined biomarkers was significantly greater than that for each biomarker individually （P < 0.05）. Conclusions Serum levels of IL-6， IL-8， TREM1， uPAR， and presepsin are significantly elevated in patients with septic shock， which may aid in the clinical diagnosis of the condition. The combined use of these five biomarkers enhances the accuracy of diagnosing septic shock.