We have investigated predictive value of HbA1c for hospital mortality and length of stay (LOS) in patients with type 2 diabetes admitted because of sepsis. A prospective observational study was implemented in a university hospital, 286 patients with type 2 diabetes admitted with sepsis were included. Leukocyte count, CRP, admission plasma glucose, APACHE II and SOFA score were noted at admission, HbA1c was measured on the first day following admission. Hospital mortality and hospital length of stay (LOS) were the outcome measures. Admission HbA1c was significantly lower in surviving patients than in non-survivors (median 8.2% versus 9.75%, respectively; P<0.001). There was a significant correlation between admission HbA1c and hospital LOS of surviving patients (r=0.29; P<0.001). Logistic regression showed that HbA1c is an independent predictor of hospital mortality (odds ratio 1.36), together with female sex (OR 2.24), APACHE II score (OR 1.08) and SOFA score (OR 1.28). Multiple regression showed that HbA1c and APACHE II score are independently related to hospital LOS. According to our results, HbA1c is an independent predictive factor for hospital mortality and hospital LOS of diabetic patients with sepsis.