Objective: To investigate the correlations between the lactate acid and procalcitonin levels and prognosis of septic shock. Methods: A total of 70 critically ill patients with confirmed septic shock admitted to the intensive care unit (ICU) were enrolled in the present study. They were assigned to the survival control group or the death group according to the clinical outcomes after standard care. The differences in the Acute Physiology and Chronic Health Evaluation II (APACHE II) score and the levels of blood lactic acid and procalcitonin at 0 h, 6 h and 24 h after admission to the ICU, respectively were compared among the patients in the two groups. Pearson correlation was employed to assess the association of diverse outcomes with the levels of blood lactic acid and procalcitonin and the APACHE II score, and the association of the APACHE II score with the blood lactic acid and procalcitonin levels as well. Results: The blood lactate acid and procalcitonin levels at different time points were significantly lower among the patients in the survival control group than those in the death group (All P=0.000); as compared tothe patients in the death group, a substantial reduction in the APACHE II score was noted among those in the survival control group (P=0.000); among all the patients, their prognosis was negatively correlated with the blood lactate acid level (r=-0.71, P=0.014) the procalcitonin level (r=-0.84, P=0.019) and the APACHE II score (r=-0.74, P=0.009) whereas the APACHE II score was positively correlated with the blood lactate acid level (r=0.68, P=0.006) and the procalcitonin level (r=0.77, P=0.012). The receiver operating characteristics (ROC) curves indicated that the levels of blood lactic acid (P=0.013) and procalcitonin (P=0.009) were significantly predictive of the mortality of the patients with septic shock. Conclusion: The blood lactate acid and procalcitonin levels were correlated with prognosis of patients with septic shock, with higher levels of blood lactate acid and procalcitonin indicating worse prognosis.