Objective To assess the clinical value of systemic vascular resistance index (SVRI) combined with serum procalcitonin (PCT) and sequential organ failure assessment (SOFA) score in the early diagnosis of sepsis. Methods A retrospective study was conducted. The data of critical patients admitted to Department of Critical Care Medicine of the Third People's Hospital of Hechi from November 2013 to April 2016 were enrolled. The clinical data were recorded as follows: gender, age, infection site, SOFA score, serum PCT level (enzyme linked fluorescence analysis) within 1 hour after intensive care unit (ICU) admission, hemodynamics parameters, including mean arterial pressure (MAP), central venous pressure (CVP), cardiac index (CI), SVRI, global end diastolic volume index (GEDVI), extravascular lung water index (EVLWI), which were monitored by pulse indicator continuous cardiac output (PiCCO) after ICU admission. The patients were divided into sepsis and non-sepsis groups according to the diagnostic criteria of sepsis. Septic patients were divided into low SVRI group, normal SVRI group, and high SVRI group according to SVRI normal value (170-240 kPa·s·L-1·m-2), and the differences in parameters among the three groups were compared. The correlations between SVRI and various parameters were analyzed by using Pearson correlation analysis. The receiver operating characteristic curve (ROC) was plotted to evaluate the diagnostic efficiency of each parameter. Results Totally 103 critical patients were enrolled, 55 in sepsis group, and 48 in non-sepsis group. Compared with non-sepsis group, SVRI in septic group was significantly lowered (kPa·s·L-1·m-2: 146.56±45.17 vs. 188.04±56.27), and serum PCT was significantly increased (μg/L: 10.43±6.17比0.32±0.11) with statistically significant differences (both P < 0.05). In 55 sepsis patients, there were 21 in low SVRI group, 19 in normal SVRI group, and 15 in high SVRI group. There were no statistically significant differences in gender, age and infection site among the three groups, indicating that the baseline data among all groups was balanced with comparability. SOFA score, PCT, and CI in the low SVRI group were significantly higher than those of normal SVRI and high SVRI groups [SOFA: 10.57±2.89 vs. 5.73±2.28, 5.73±2.15, PCT (μg/L): 24.15±12.43 vs. 7.18±5.05, 7.39±4.38, CI (mL·s-1·m-2): 71.01±9.67 vs. 62.01±8.34, 62.51±8.67, all P < 0.05], but no significant difference was found between the normal SVRI group and high SVRI group. There was no statistically significant difference in MAP, CVP, EVLWI, and GEDVI among the three groups. It was shown by Pearson correlation analysis that SVRI was negatively correlated with PCT, SOFA score, and CI (r value was -0.622, -0.598, -0.398, all P = 0.000). It was shown by ROC curve that area under ROC curve (AUC) of PCT combined with SVRI for diagnosis of sepsis was higher than that of PCT or SVRI alone (0.943 vs. 0.911, 0.884). When the cut-off value of PCT was 3.79 μg/L, and cut-off value of SVRI was 156.81 kPa·s·L-1·m-2, the sensitivity and specificity were 94.6% and 92.3% respectively. Conclusions For sepsis patients, SVRI is related to PCT and SOFA score. Combined monitoring of PCT, SVRI, SOFA score can accurately reflect the severity of sepsis patients, guide diagnosis and treatment, and estimate prognosis. The efficacy of PCT combined with SVRI in the early diagnosis of sepsis is better than that of the two alone.