Objective To evaluate the predicting effect of quick Sequential Organ Failure Assessment (qSOFA) on septic shock, and investigate the probability of improving the predicting effect. Methods Patients with sepsis diagnosed in Emergency Department from July 2015 to June 2016 were enrolled. They were divided into shock group and non-shock group based on whether or not they had septic shock during 72 hours after admission. The multivariate logistic regression analysis was used to find out the independent risk factors affecting the incidence of septic shock. Receiver operating characteristic (ROC) curve was used to analyze those risk factors. Modified Early Warning Score (MEWS), Mortality in Emergency Department Sepsis Score (MEDS), Sequential Organ Failure Assessment (SOFA), Acute Physiology and Chronic HealthEvaluation (APACHE)Ⅱ and qSOFA were also compared with ROC curve analysis. The possibility of improvement of qSOFA predicting effect was discussed. Results A total of 821 patients were enrolled, with 108 in septic shock group and 713 in non-septic shock. The result of multivariate logistic regression analysis indicated that respiratory rate, systolic blood pressure, pH value, oxygenation index, lactate, albumin, Glasgow Coma Score and procalcitonin were the independent risk factors (P<0.05). The result of ROC analysis showed that the area under curve (AUC) of pH value, lactate and procalcitonin was 0.695, 0.678 and 0.694, respectively. Lactate had the highest value of specificity (0.868), positive predictive value (0.356) and positive likelihood ratio (3.644), while the sensitivity (0.889) and negative predictive value (0.961) of procalcitonin were the highest. MEWS, MEDS, SOFA, APACHEⅡ and qSOFA were compared with ROC. SOFA had the best predicting effect with the statistical results of AUC (0.833), sensitivity (0.835), specificity (0.435), positive predictive value (0.971), negative predictive value (0.971), and positive likelihood ratio (5.048); and MEWS had the highest negative likelihood ratio (0.581). qSOFA did not show a best predicting value. Conclusion qSOFA is not the best choice to predict the possibility of septic shock, but its predicting value might be improved when combined with pH value, lactate and procalcitonin.