Objective In this study, we aimed to evaluate the combined diagnostic value of procalcitonin (PCT), C-reactive protein (CRP), and serum amyloid A (SAA) in sepsis caused by urinary tract infection. Method A total of 80 patients with urosepsis who were hospitalized were included in the study group, and 80 patients with urinary tract infection without sepsis were included in the control group. We collected the PCT, SAA, and CRP levels of patients following admission. Subsequently, we conducted a comparative analysis to assess the specificity, accuracy, and sensitivity of combined diagnostic approaches in contrast to individual diagnostic methods for blood PCT, SAA, and CRP. Results The levels of PCT, SAA, and CRP in the study group were significantly higher than those in the control group, and the differences were statistically significant (P < 0.01). Multi-factor logistic regression analysis revealed that the levels of PCT (P = 0.003) and SAA (P = 0.014) were associated with urosepsis. The sensitivity of PCT was 87.133% and the specificity was 93.066%, which were higher than that of SAA and CRP. The specificity of the combined detection of the three was 95.670%, which was higher than that of PCT, SAA, and CRP alone. Correlation analysis revealed that PCT had a significant positive correlation with CRP and SAA (P < 0.01), and a weak correlation with white blood cell count (WBC) and fibrinogen (FIB) (P = 0.03 for WBC, P = 0.04 for FIB). Conclusion PCT, SAA, and CRP indicators in patients with urosepsis are significantly elevated, and all three are valuable in the diagnosis of urosepsis. PCT alone has good diagnostic efficiency for urosepsis, and a certain correlation with other inflammatory factors. The diagnostic efficacy of the three indicators in combination is better than that of any one of the three, and is worthy of widespread clinical application.