We found that the overall 28-day mortality was 46% (93 out of 203 patients). There was a significantly positive correlation between mortality rate and plasma IL-6 (survivors vs. nonsurvivors; 74 (4.4 to 1,718) vs. 206 (19 to 5,000) pg/ml, P < 0.05), lactate (survivors vs. nonsurvivors; 1.65 (0.7 to 11.61) vs. 2.47 (0.94 to 19.13) mmol/l, P < 0.05), but not CRP levels (P = 0.24). Compared with the patients with plasma IL-6 <100 pg/ml, septic patients with IL-6 levels ≥100 were associated with an increased 28-day mortality with the odd ratio of 2.99 (95% CI 1.42 to 6.29, P < 0.05). We also found that plasma IL-6 levels were well correlated with APACHE II (P < 0.05), SAPS II (P < 0.05), and SOFA (P < 0.05) scores.