Because of high and rising prevalence of severe infections and sepsis, these also play an important role in the emergency department (ED). A prospective observational study was performed. We included patients which came to the ED with a suspected severe infection. We compared the prognostic value of the clinical scores APACHE II, SOFA, and MEDS, and the biomarkers C-reactive protein (CRP), procalcitonin (PCT), and interleukin 6 (IL-6) by using cross classification tables and receiver operating characteristic curves (ROC). In total 128 patients were included into the study. MEDS, APACHE II and CRP showed higher significant values of the ROC curve than SOFA, PCT and IL6. The area under the receiver operating characteristics curves of MEDS, APACHE II and CRP were 0,818; 0,827 and 0,818 for the 28-day mortality. In patients with suspected severe infection in emergency department MEDS-, APACHE II score and CRP are a valuable and significant tool for the prediction of the 28-day-mortality.