Abstract: OBJECTIVE To investigate the prognostic value of lactate clearance rate during the first 24 hours(H24) of resuscitation in septic shock patients,in order to better guide the treatment of fluid resuscitation. METHODS Prospective study on 34 patients with septic shock hospitalized in the ICU from Jun. 2014 to Jun. 2015 were implemented. The lactate concentration was measured at resuscitation began (H0) and at H6, H24 after resuscitation, and the lactate clearance rate was calculated. According to the mortality rate in 28 days, all the patients were divided into death group and survival group. There were 10 patients in death group and 24 patients in survival group. The lactate concentration, lactate clearance rate, APACHEⅡ score and duration of mechanical ventilation of patients were compared at H6 and H24 after resuscitation. Prognostic value of lactate clearance rate was analyzed by receiver operating characteristic(ROC) curve. RESULTS There was no significant difference in the initial lactate, lactate clearance rate of H6 and the duration of mechanical ventilation between two groups. The lactate concentration of H6 and H24 after resuscitation and H24 lactate clearance rate in death group were (6.79±4.39)(6.13±3.75)mmol/L and (22.10±34.73)%, they were rsspectively(3.27±2.69)(2.33±2.44)mmol/L and (50.74±20.25)%, in the survival group(P<0.05). The area under the curve(AUC) of ROC curve for H6 and H24 lactate clearance rates were 0.65 and 0.76 respectively. CONCLUSION During the first H24in the ICU, lactate clearance rate at H24 after resuscitation is closely associated with prognosis. If lactate clearance rate does not reach the standard, resuscitation therapy should be kept using, even after the golden H6.